O-Ring Size Calculator | Groove Design & Seal Dimensions
Design better seals faster with this comprehensive O-Ring Size Calculator. Instantly find exact O-ring dimensions, calculate optimal groove/gland geometry, check compression squeeze, installation stretch, and gland fill percentage.
Includes AS568 & ISO 3601 standards lookup, material compatibility guide, visual diagrams, and full engineering reports. Works in both metric and imperial units — the complete tool for engineers and technicians working on hydraulic, pneumatic, and static/dynamic sealing applications.
O-Ring Size Calculator
Compression • Stretch • Gland Fill • Groove Design • Material Selector
Enter any two known dimensions. The third will be calculated. Tip: OD = ID + 2×CS
Formulas Used in This Calculation
▼O-Ring Basic Dimensions
Enter O-ring dimensions and application details to calculate recommended groove geometry for leak-free sealing.
Groove Design Formulas
▼Groove Dimension Calculations
Standard references: Parker O-Ring Handbook ORD 5700, AS568A, ISO 3601-2
Determine the percentage of squeeze applied to the O-ring cross-section when installed in a groove. Ideal range varies by application.
Compression Formula & Reference Ranges
▼Squeeze % Formula
| Application | Min % | Optimal % | Max % |
|---|---|---|---|
| Static Radial Seal | 15% | 20-25% | 30% |
| Static Face Seal | 20% | 25-30% | 35% |
| Dynamic Reciprocating | 10% | 12-18% | 22% |
| Dynamic Rotary | 8% | 10-15% | 18% |
| Vacuum Seal | 25% | 30% | 35% |
Calculate the installation stretch when fitting an O-ring over a piston or shaft. Keep stretch below 5% for dynamic seals; up to 8% for static.
Stretch Formula & Thinning Effect
▼Installation Stretch
Cross-Section Thinning Due to Stretch
When an O-ring is stretched, its cross-section becomes thinner, reducing effective compression. This is why high stretch is undesirable in sealing applications.
Calculates what percentage of the groove volume is occupied by the O-ring. Target: 75-85% for dynamic, 85-95% for static. Never 100% — leave room for thermal expansion.
Gland Fill & Volume Formulas
▼Gland Fill Calculation
Thermal Expansion Adjustment
Where α = thermal expansion coefficient (~1.8×10-4 /°C for NBR). At high temperatures, gland fill can exceed 100% causing hardware damage.
Select your operating conditions to find the best O-ring material. Click a material card to view full details.
All available materials — click for detailed specifications:
Search by dash number or enter dimensions to find the nearest standard O-ring size. Includes AS568, ISO 3601, and common metric sizes.
Generate a complete summary of all your calculations, then copy or print for your records.
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O-Ring Size Calculator — Complete User Guide
Step-by-step instructions • All formulas explained • AS568 • ISO 3601 • Metric & Imperial • Groove design • Material selector
What Is an O-Ring Size Calculator?
An O-ring size calculator is an engineering and industrial sealing tool designed to help engineers, maintenance technicians, machinists, and procurement teams determine the correct O-ring dimensions, groove geometry, compression, stretch, and gland fill percentage for any sealing application. Whether you are working on a hydraulic system, pneumatic cylinder, automotive component, or industrial machine, selecting the wrong O-ring leads directly to leakage, premature seal failure, and costly downtime.
Leading manufacturers such as Parker Hannifin, Trelleborg, ERIKS, SKF, and Ceetak — including specialist divisions like Prädifa Technology Division — publish O-ring sizing guidance and engineering handbooks. This free online O-ring sizing tool consolidates those engineering principles into a single, easy-to-use calculator that covers everything from basic dimension calculation to advanced groove design and material compatibility analysis.
Key User Pain Points & How This Calculator Solves Them
Engineers and technicians encounter the following challenges when selecting and designing O-ring seals. Here is how this O-ring sizing tool addresses each one directly:
O-Ring & Groove Anatomy Diagram
The diagram below illustrates the critical dimensions every O-ring seal calculation depends on. Understanding these terms is essential before using any section of the calculator.
Figure: O-ring anatomy showing Inner Diameter (ID), Outer Diameter (OD), Cross-Section (CS), groove depth, groove width, and the critical clearance gap that determines extrusion risk. Used by engineers following Parker, Trelleborg, ERIKS, SKF, and Ceetak sealing design guidelines.
Step-by-Step User Guide
Follow this guide for each section (tab) of the O-Ring Size Calculator. Every input field is explained with its unit, purpose, and common mistakes to avoid.
Step 0 — Select Your Unit System (Always Do This First)
At the top of the calculator, choose between mm (Metric) and inch (Imperial) before entering any values. This toggle controls every input field and output label across all tabs.
Choose mm for Metric (ISO 3601, DIN 3771)
Use millimetres when working with metric O-rings sourced from European suppliers (ERIKS, Trelleborg, SKF), ISO 3601 standards, or DIN 3771 specifications. All dimensions will display in mm.
Choose inch for Imperial (AS568, BS 1806)
Use decimal inches when working with AS568 (USA/Aerospace), BS 1806 (British), or Parker NH series O-rings. Dimensions display in decimal inches (not fractional). Example: 1.000 in, not 1 ¼ in.
💡 Common mistake: entering metric mm values after switching to the inch setting causes dramatically wrong results.Step 1 — O-Ring Size Finder Tab
Use this section to calculate any missing O-ring dimension, find the nearest standard size, and identify the correct AS568 dash number or equivalent metric code.
Input Fields
| Field | Unit | Description | When Required |
|---|---|---|---|
| Inner Diameter (ID) | mm / in | The internal diameter of the O-ring when measured at rest (free state). Not the groove diameter. | Required if OD is not known |
| Outer Diameter (OD) | mm / in | The external diameter. Equals ID + 2×CS. Often stamped on manufacturer packaging. | Required if ID is not known |
| Cross-Section (CS) | mm / in | The diameter of the O-ring cord / wire thickness. Also called “cord diameter” or “section diameter.” | Required if ID & OD are both unknown |
| Application Type | — | Select Static, Dynamic (Reciprocating), Dynamic (Rotary), or Face/Axial Seal. Affects standard size recommendations. | Always select |
| Preferred Standard | — | AS568, ISO 3601, BS 1806, JIS B2401, or DIN 3771. Determines which size database is matched. | Always select |
Outputs Explained
- Calculated ID, OD, CS — The missing dimension, computed from the two known values.
- Circumference — Mean circumference = π × (ID + CS). Useful for checking against a measuring tape.
- Volume — O-ring material volume in cm³, used for gland fill cross-checks and material cost estimation.
- Nearest AS568 Size — The closest standard dash number, displayed with the five surrounding sizes for comparison.
Step 2 — Groove / Gland Calculator Tab
This section calculates the recommended groove depth, groove width, corner radius, gland diameter, and surface finish (Ra value) for machining the correct housing groove. This is the most critical step for preventing leakage and extrusion.
Input Fields
| Field | Unit | Description |
|---|---|---|
| O-Ring CS | mm / in | Cross-section of the chosen O-ring. All groove dimensions scale from this value. |
| O-Ring ID | mm / in | O-ring inner diameter (for reference and stretch check). |
| Bore / Housing Diameter | mm / in | The internal diameter of the housing bore. Used to calculate the gland groove diameter for piston or rod seals. |
| Seal Type | — | Piston Seal (inside bore), Rod Seal (outside shaft), Face Seal, or Dovetail Groove. Each requires different groove geometry. |
| Motion Type | — | Static (no movement), Dynamic Reciprocating (back-and-forth), or Dynamic Rotary. Dynamic seals need wider grooves and tighter tolerances. |
| Max Pressure | bar / psi | Operating system pressure. Triggers backup ring recommendation at high pressures (>150 bar / >2,000 psi for 70 Shore A NBR). |
| Target Squeeze % | % | The desired compression percentage. Preset options range from 12% (light dynamic) to 25% (high-seal static). See recommended ranges below. |
| Material Hardness | Shore A | Durometer of the O-ring compound (60A to 90A). Harder compounds resist extrusion at higher pressures with larger clearance gaps. |
Outputs Explained
- Groove Depth — Radial dimension of the groove. Directly controls the achieved squeeze percentage.
- Groove Width — Axial length of the groove. Must accommodate the uncompressed O-ring with room to fill under compression.
- Corner Radius — Minimum recommended fillet radius to prevent O-ring cutting during installation and operation.
- Gland Diameter — The groove diameter machined into the piston or bore, calculated from bore diameter and groove depth.
- Actual Squeeze — The squeeze percentage that will result from the calculated groove depth. Colour-coded pass/warn/fail.
- Gland Fill % — Percentage of groove volume occupied by the O-ring cross-section. Must stay below 90–95%.
- Surface Finish (Ra) — Recommended Ra surface roughness for the groove walls (1.6 μm static; 0.4 μm dynamic).
Step 3 — Compression (Squeeze) Calculator Tab
Enter the O-ring cross-section and the actual groove depth (as machined) to calculate the real squeeze percentage and determine whether the seal will perform reliably.
Input Fields
- O-Ring CS [mm / in] — Nominal cross-section diameter from the O-ring manufacturer's datasheet.
- Groove Depth [mm / in] — Actual measured or designed radial depth of the groove. Must be less than CS.
- Application — Static, Dynamic Reciprocating, Dynamic Rotary, Face Seal, or Vacuum. Determines the recommended squeeze range used for pass/fail evaluation.
Recommended Compression Ranges by Application
Squeeze % Safe Range Indicator
| Application Type | Min % | Optimal Range | Max % | Risk if Exceeded |
|---|---|---|---|---|
| Static Radial Seal | 15% | 20–25% | 30% | Extrusion, compression set |
| Static Face / Axial Seal | 20% | 25–30% | 35% | Extrusion, hardware damage |
| Dynamic Reciprocating | 10% | 12–18% | 22% | Friction, wear, spiral failure |
| Dynamic Rotary | 8% | 10–15% | 18% | Heat build-up, rapid wear |
| Vacuum Seal | 25% | 28–32% | 37% | Outgassing, permeation failure |
| Below minimum (< min) | — | Insufficient | — | Immediate leakage, no sealing force |
Step 4 — Stretch Calculator Tab
When an O-ring is fitted over a piston or shaft whose diameter is larger than the O-ring's free-state ID, it stretches. This stretching thins the cross-section and reduces effective compression. The stretch calculator quantifies this effect.
Input Fields
- O-Ring Free ID [mm / in] — The nominal inner diameter in its resting, un-stretched state (from the manufacturer's catalogue or AS568 specification).
- Groove / Shaft Diameter [mm / in] — The diameter of the piston groove or shaft over which the O-ring will be fitted. This is the installed inner diameter.
- Application — Static Piston, Dynamic Piston, or Rod Seal. Maximum allowable stretch differs between static (8%) and dynamic (5%) applications.
Step 5 — Gland Fill Calculator Tab
Gland fill percentage is the ratio of the O-ring's cross-sectional area to the groove's cross-sectional area. This calculator also projects fill percentage at elevated operating temperature to detect thermal overfill before it causes hardware damage.
Input Fields
- O-Ring CS [mm / in] — Cross-section diameter.
- O-Ring ID [mm / in] — Inner diameter (used to compute O-ring volume).
- Groove Width [mm / in] — Axial length of the groove cavity.
- Groove Depth [mm / in] — Radial depth of the groove cavity.
- Operating Temperature [°C] — Maximum service temperature. The calculator applies an approximate volumetric thermal expansion coefficient for elastomers (~1.8×10−4 /°C for NBR) to estimate fill at temperature.
- Application — Static or Dynamic. Optimal fill ranges differ by application type.
| Fill % | Status | Risk |
|---|---|---|
| < 65% | 🔴 Under-fill | O-ring rolls, shifts, fails to seal under pressure. Use larger CS or reduce groove volume. |
| 65–75% | 🟡 Marginal | Acceptable in some low-pressure static applications, but not recommended as a design target. |
| 75–85% | ✅ Optimal (Dynamic) | Recommended range for dynamic seals. Adequate room for compression and thermal expansion. |
| 85–95% | ✅ Optimal (Static) | Recommended range for static seals where thermal expansion headroom must be verified. |
| > 95% | 🔴 Over-fill (DANGER) | Thermal expansion will cause 100% fill, splitting the housing or extruding the seal. Immediate redesign required. |
Step 6 — Material Selector Tab
Select your operating fluid, minimum temperature, and maximum temperature to filter compatible elastomers. The tool ranks materials from most to least recommended for your conditions.
Supported Fluid Types
- Hydraulic oil (mineral-based) — Most common in industrial hydraulic systems (Parker, Bosch Rexroth)
- Diesel / petroleum fuel — Automotive, marine, and industrial fuel systems
- Water and aqueous solutions — Including potable water (food-grade / NSF 61 required)
- Steam (high temperature) — Requires EPDM or AFLAS; NBR and FKM are unsuitable above 150°C steam
- Brake fluid (DOT 3/4/5) — Requires EPDM; petroleum-based seals will swell catastrophically
- Aggressive chemicals and acids — Viton (FKM) or FFKM (Kalrez/Simriz) for harsh chemical service
- Pneumatic air and gases — NBR and Silicone are commonly specified
- Refrigerants (HFCs, HCFCs) — Neoprene (CR) or HNBR; verify with the specific refrigerant
- Natural gas / sour gas (H2S) — HNBR or AFLAS; standard NBR suffers H2S-induced degradation
Step 7 — Standards Lookup Tab
Search the built-in AS568 database by dash number or measured dimensions to identify a standard O-ring size without downloading any PDF or Excel chart.
How to Search
Search by Dash Number
Enter the AS568 dash number (e.g. 214 or AS568-214) in the first field. Results show the exact dimensions with Class 1 tolerances. If the part number format is -214, enter just 214.
Search by Measured Dimensions
Enter your measured ID and/or CS. The calculator finds the 7 nearest standard sizes, ranked by dimensional proximity. The closest match is highlighted. Use this to find a standard replacement for a custom or metric O-ring.
Show All Sizes
Click “Show All Sizes” to display the complete AS568 database — from dash -006 (smallest) to dash -450 (large boss sizes), covering all four standard CS series: 0.74 mm, 1.78 mm, 2.62 mm, 3.53 mm, and 5.33 mm.
Step 8 — Engineering Report & Export Tab
Once all your calculations are complete, navigate to the Report tab and click Generate Report. The calculator compiles every result from all tabs into a single formatted engineering document that you can copy to clipboard or print as a PDF for your records.
All Formulas Used in This Calculator — Explained
Every result produced by this O-ring size calculator is derived from the following standard engineering formulas, cross-referenced with AS568A, ISO 3601, and the Parker O-Ring Handbook (ORD 5700). Each formula is shown in its standard mathematical form with a worked example.
Formula 1 — Basic Dimension Relationship
The three fundamental O-ring dimensions are rigidly linked. Knowing any two allows the third to be calculated with certainty. This is the starting point for all O-ring sizing work.
📄 Worked example: If ID = 25.00 mm and CS = 2.62 mm, then OD = 25.00 + 2×2.62 = 30.24 mm. AS568-215 has ID = 23.90 mm, CS = 2.62 mm → OD = 29.14 mm. Units: mm (Metric) or decimal inch (Imperial/AS568).
Formula 2 — Compression (Squeeze) Percentage
Compression percentage is the most important single number in O-ring engineering. It determines whether the seal will leak (too low) or extrude and fail (too high). This formula is used by Parker, Trelleborg, ERIKS, SKF, and every major sealing manufacturer worldwide.
📄 Worked example: CS = 2.62 mm, Groove Depth = 2.10 mm. Squeeze = (2.62 − 2.10) / 2.62 × 100 = 19.8% → Optimal for a static radial seal. Actual squeeze = 0.52 mm. Reference: Parker O-Ring Handbook ORD 5700, Table 2-2; AS568A Appendix A.
Formula 3 — Installation Stretch Percentage
When an O-ring is stretched over a piston whose groove diameter is larger than the O-ring free-state ID, the cross-section thins in proportion to the stretch. This thinning reduces the effective compression and can cause premature leakage.
📄 Worked example: O-ring ID = 25.00 mm, Groove diameter = 26.50 mm. Stretch = (26.50−25.00)/25.00 × 100 = 6.0% → Warning for dynamic; acceptable for static only. CS thinning ≈ 1/√1.06 ≈ 97.1% of original CS. If CS = 2.62 mm, installed CS ≈ 2.54 mm.
Formula 4 — Gland Fill Percentage
The gland fill percentage determines whether an O-ring will fit its groove safely at all operating temperatures. An over-filled groove has no room for thermal expansion; an under-filled groove results in a wobbly seal that leaks under pressure.
📄 Worked example: CS = 2.62 mm, Groove Width = 3.60 mm, Groove Depth = 2.10 mm. Aring = π×2.62²/4 = 5.39 mm². Agroove = 3.60×2.10 = 7.56 mm². Fill = 5.39/7.56×100 = 71.3% → Marginal; within acceptable range for dynamic seal.
Formula 5 — Groove Depth from Target Squeeze
When designing a new groove, the required depth is calculated directly from the O-ring CS and the desired squeeze percentage. This formula is the inverse of Formula 2.
📄 Worked example: CS = 2.62 mm, target squeeze 20%. Depth = 2.62×(1−0.20) = 2.10 mm. Width (static) = 2.62×1.65 = 4.32 mm. Width (dynamic) = 2.62×2.0 = 5.24 mm. Corner radius min = 0.1×2.62 = 0.26 mm.
Formula 6 — O-Ring Volume
The toric (toroidal) volume of an O-ring is required for accurate gland fill calculations and for estimating material cost or weight. This formula uses the Pappus centroid theorem for a circular cross-section.
📄 Worked example: CS = 2.62 mm, ID = 25.00 mm. V = 2×9.87×(2.62²/4)×(25/2+2.62/2) = 2×9.87×1.715×13.81 = 466.8 mm³ = 0.467 cm³. Density of NBR ≈ 1.20 g/cm³ → mass ≈ 0.56 g per O-ring.
Formula 7 — Thermal Expansion Adjustment
At elevated operating temperatures, elastomers expand significantly. Failure to account for thermal expansion is a primary cause of gland overfill and housing cracking in high-temperature applications such as steam, hydraulic oil above 80°C, or automotive engine bay seals.
📄 Where α = thermal expansion coefficient per °C (NBR/Buna: ~1.8×10−4; FKM/Viton: ~1.5×10−4; Silicone: ~2.0×10−4). ΔT = operating temperature − 23°C (reference). Example: Fill = 78% at 23°C, NBR, T = 120°C. ΔT = 97°C. Fillhot = 78% × (1 + 3×1.8×10−4×97) = 78% × 1.0524 = 82.1% → Still acceptable.
O-Ring Sizing Standards Reference Chart
The following table summarises the major O-ring sizing standards used globally. Engineers working in the UK, USA, Japan, and Europe need to understand which standard applies to their application before selecting dimensions or ordering from suppliers such as ERIKS, Parker, SKF, Trelleborg, Ceetak, or Prädifa Technology Division.
| Standard | Origin | Unit | CS Series | Dash / Code Format | Common Users |
|---|---|---|---|---|---|
| AS568A | USA (SAE) | Inch | 0.070, 0.103, 0.139, 0.210 in | -004 to -475, -901 to -932 | Aerospace, Defence, Industrial (USA/UK) |
| ISO 3601-1 | International | mm | 1.78, 2.62, 3.53, 5.33, 6.99 mm | A-series (e.g. A 12×2) | European industrial, automotive OEM |
| BS 1806 | UK (BSI) | Inch | Equivalent to AS568 series | BS 1806 size codes | UK engineering, legacy systems |
| JIS B2401 | Japan (JSA) | mm | P, G, S, V series | P3, P4 … P400; G25 … G300 | Japanese OEM, Asian industrial |
| DIN 3771 | Germany (DIN) | mm | 1, 1.5, 2, 2.5, 3, 4, 5, 6 mm CS | ID×CS (e.g. 50×3) | German/European machinery, hydraulics |
| ISO 3601-3 | International | mm / in | Tolerance classes A & B | As per ISO 3601-1 | Precision seals, aerospace |
AS568 Cross-Section Series — Quick Reference
| Dash Series | Nominal CS (in) | Nominal CS (mm) | Typical ID Range | Application |
|---|---|---|---|---|
| -0xx (001–099) | 0.040–0.070 in | 1.02–1.78 mm | Up to ~0.75 in | Small fittings, instruments |
| -1xx (100–199) | 0.103 in | 2.62 mm | 0.04–1.11 in | General purpose, pneumatic |
| -2xx (200–299) | 0.139 in | 3.53 mm | 0.49–4.23 in | Hydraulic, industrial |
| -3xx (300–399) | 0.210 in | 5.33 mm | 1.24–4.48 in | Large hydraulic, flanged fittings |
| -4xx (400–475) | 0.275 in | 6.99 mm | 1.86–25.94 in | Boss fittings, large diameter |
| -9xx (901–932) | 0.275–0.550 in | 6.99–13.97 mm | Extra large | Large flanges, pressure vessels |
O-Ring Material Selection Guide
Choosing the correct elastomer is as critical as choosing the correct size. The following table summarises the eight most common O-ring materials, their temperature ranges, hardness options, and key compatible fluids. Use this alongside the Material Selector tab in the calculator.
| Material | Abbr. | Temp. Range | Hardness (Shore A) | Best For | Avoid |
|---|---|---|---|---|---|
| Nitrile (Buna-N) | NBR | −40°C to +120°C | 40–90A | Hydraulic oil, mineral oil, petroleum fuel, water, air — the most widely used elastomer in industrial sealing | Brake fluids (DOT), ketones, aromatic solvents, ozone exposure |
| Viton (FKM) | FKM | −20°C to +200°C | 60–90A | High temperature applications, aggressive chemicals, HFD hydraulic fluids, fuels, chemical process plants | Ketones, low-temperature applications, amines, steam above 150°C |
| EPDM | EPDM | −50°C to +150°C | 40–80A | Water, steam (up to 150°C), brake fluid (DOT 3/4), phosphate ester fluids, outdoor weathering and ozone | Petroleum oils, hydrocarbon fuels, mineral-based hydraulic fluid |
| Silicone (VMQ) | VMQ | −65°C to +175°C | 30–80A | Extreme temperature range, food-grade applications, medical devices, dry heat, pneumatic air systems | High-pressure dynamic seals (poor abrasion resistance), petroleum oils, steam, aromatic hydrocarbons |
| Neoprene (CR) | CR | −40°C to +100°C | 40–90A | Refrigerants (CFC/HCFC), ozone, weathering, moderate petroleum exposure, outdoor sealing | Strong acids, aromatic hydrocarbons, ketones, esters |
| PTFE / FFKM | PTFE | −200°C to +260°C | N/A | Ultra-high chemical resistance across virtually all media, clean-room, semiconductor, pharmaceutical | Not elastomeric — used as backup rings or energised seals. Not for standard groove designs. |
| HNBR | HNBR | −40°C to +150°C | 60–90A | Automotive AC systems, sour gas (H2S), geothermal, refrigerants, engine coolants, oilfield applications | Aromatic solvents, strong oxidising acids, chlorinated hydrocarbons |
| AFLAS (TFE/P) | AFLAS | −5°C to +200°C | 70–90A | Amines, H2S sour service, steam, caustic solutions, oilfield downhole applications (NH Max Spare Ltd sealing solutions) | Ketones, some esters, low-temperature environments |
Common Mistakes & How to Avoid Them
These are the most frequent errors made when using an O-ring size calculator or specifying O-ring seals. Each mistake is paired with the correct approach.
ACCURACY NOTE — Engineering Guidance Tool
All results produced by this O-ring size calculator are based on internationally recognised engineering formulas from AS568A, ISO 3601-1/2, and the Parker O-Ring Handbook (ORD 5700). Calculations are intended as design guidance for engineers and should be verified against the specific manufacturer's datasheet (Parker, Trelleborg, ERIKS, SKF, Ceetak, Prädifa Technology Division) before production or safety-critical use. Material thermal expansion values are approximate averages — actual values vary by compound formulation, durometer, and supplier. The tool does not account for surface finish effects on friction, long-term compression set, material swell in specific chemical media, or tolerance stack-up beyond the formulas stated. For critical hydraulic, pneumatic, vacuum, or high-pressure applications, always consult a qualified sealing engineer.
Frequently Asked Questions (FAQ)
Answers to the most common questions about O-ring sizing, groove design, standards, and materials.
Use the Free O-Ring Size Calculator
Calculate compression, stretch, gland fill, groove dimensions, and find your AS568 or metric O-ring size — all in one free online engineering tool.
O-Ring Size Calculator User Guide — covering AS568, ISO 3601, BS 1806, JIS B2401, DIN 3771, hydraulic, pneumatic, static, dynamic, face, piston, rod, and vacuum sealing applications. References: Parker O-Ring Handbook ORD 5700; Trelleborg Sealing Solutions Engineering Guide; ERIKS O-Ring Technical Manual; AS568A (SAE); ISO 3601-1:2012; BS ISO 3601-1. For engineering support contact your local sealing distributor or specialist such as Ceetak, NH Max Spare Ltd, or Prädifa Technology Division (Trelleborg).
