DIN 3771 Silicone O-rings
Manufacturer & Custom Solutions

DIN 3771 Silicone O-rings

German DIN 3771 metric O-rings are a staple in European hydraulic and pneumatic systems. ZSR Silicone produces these seals with tight tolerances using VMQ, FVMQ and custom-blended silicone compounds. Whether you need standard sizes or custom dimensions, we can help.

  • MOQ: Flexible / Low MOQ Support
  • Lead Time: Prototype in 2-5 Days
  • Certifications: FDA, LFGB, ISO 9001, ROHS, REACH
  • Material: VMQ, FVMQ, LSR, HCR / HTV
  • Hardness: 30 to 80 Shore A (customizable)
  • Temperature: -60°C to 230°C (special grades to 300°C)
  • Custom Sizes: Per Your Drawing
  • Tooling: In-house mold design and machining
  • Samples: Free samples available

FDA 21 CFR 177.2600

Rubber Articles Intended for Repeated Use

LFGB 30&31

EU Food Contact Materials

USP Class VI / ISO 10993

Biocompatibility of Medical Devices

RoHS / REACH

Environmental Compliance

UL 94

Flammability of Plastic Materials

Built to Your Exact Spec

Custom Silicone O-ring Options

ImageProductTypeShort InfoAction
ISO 3601 Metric Silicone O-Rings ISO 3601 Metric Silicone O-Rings Standard & Size Metric silicone O-rings manufactured to ISO 3601 dimensions. Fits international equipment groove standards. View Details
ISO 6149 Metric Silicone O-Rings ISO 6149 Metric Silicone O-Rings Standard & Size Metric O-rings designed for hydraulic and pneumatic fluid power sealing applications under ISO 6149 standards. View Details
BS 1806 Silicone O-rings BS 1806 Silicone O-rings Standard & Size British Standard inch-size silicone O-rings. Common in UK and Commonwealth industrial equipment. View Details
DIN 3771 Silicone O-rings DIN 3771 Silicone O-rings Standard & Size German metric standard O-rings for hydraulic and pneumatic sealing in European machinery. View Details
Custom Molded Silicone O-rings Custom Molded Silicone O-rings Standard & Size Custom-shaped silicone O-rings molded to your exact drawing or sample. No standard size limitations. View Details
AS568 Silicone O-rings AS568 Silicone O-rings Standard & Size Inch-size silicone O-rings that follow the AS568 standard. Widely used in North American machinery and hydraulic systems. View Details
AN6227 Silicone O-rings AN6227 Silicone O-rings Standard & Size Aerospace-standard O-rings with small cross-section. Used in aviation and military-grade sealing. View Details
AN6230 Silicone O-rings AN6230 Silicone O-rings Standard & Size Aerospace-standard O-rings specified under AN6230 for aviation and military-grade sealing. View Details
JIS B2401 Silicone O-Ring JIS B2401 Silicone O-Ring Standard & Size Japanese industrial standard O-rings commonly used in Asian-manufactured machinery and automotive equipment. View Details
FDA Food Grade Silicone O-Rings FDA Food Grade Silicone O-Rings Grade Food-safe silicone O-rings compliant with FDA regulations. Safe for repeated food contact. View Details
Industrial Grade Silicone O-ring Industrial Grade Silicone O-ring Grade General-purpose silicone O-rings for industrial sealing. Cost-effective with reliable performance. View Details
Medical Grade Silicone O-ring Medical Grade Silicone O-ring Grade Biocompatible silicone O-rings for medical devices. Passes USP Class VI and supports sterilization. View Details
Oil-Resistant / Fuel-Resistant Silicone O-Rings Oil-Resistant / Fuel-Resistant Silicone O-Rings Special Function Modified silicone O-rings that resist swelling in oils, fuels and petroleum-based fluids. View Details
Metal Detectable Silicone O-Rings Metal Detectable Silicone O-Rings Special Function Food-safe silicone O-rings with metal-detectable additives. Protects production lines from contamination. View Details
High Temperature / Heat Resistant Silicone O-Rings High Temperature / Heat Resistant Silicone O-Rings Special Function Silicone O-rings that stay flexible at temperatures above 200°C. For ovens, engines and furnaces. View Details
VMQ Silicone O-Rings VMQ Silicone O-Rings Materials Heat and cold-resistant silicone O-rings for food, medical, automotive, and industrial applications. View Details
Fiberglass Reinforced Silicone O-rings Fiberglass Reinforced Silicone O-rings Materials High-strength silicone O-rings reinforced with fiberglass fabric. Withstands extreme heat and pressure. View Details
HCR / HTV / Solid Silicone Rubber O-rings HCR / HTV / Solid Silicone Rubber O-rings Materials Durable solid silicone rubber O-rings made by compression molding. The standard choice for general sealing. View Details
Liquid Silicone Rubber (LSR) O-rings Liquid Silicone Rubber (LSR) O-rings Materials Injection-molded liquid silicone rubber O-rings with tight tolerances and clean surfaces. Ideal for high-volume production. View Details
Platinum Cured Silicone O-rings Platinum Cured Silicone O-rings Materials Ultra-clean silicone O-rings cured with platinum catalyst. Lower extractables for food and medical use. View Details
Fluorosilicone (FVMQ) O-rings Fluorosilicone (FVMQ) O-rings Materials Fuel and oil-resistant silicone O-rings for aerospace, automotive and chemical applications. View Details
Transparent / Clear Silicone O-rings Transparent / Clear Silicone O-rings Color See-through silicone O-rings for visual inspection and clean-looking medical or food equipment. View Details
Black / White Silicone O-Rings Black / White Silicone O-Rings Color Standard black and white silicone O-rings. The most common colors for industrial and food-grade applications. View Details
Pantone Colors Silicone O-rings Pantone Colors Silicone O-rings Color Silicone O-rings in any Pantone color for branding, color-coding or aesthetic requirements. View Details
Custom Colors Silicone O-rings Custom Colors Silicone O-rings Color Silicone O-rings matched to your exact color sample or specification. View Details

Simple DIN 3771 Silicone O-rings Size Chart

  • CS: Cross-section diameter (Wire diameter)
  • ID: Inner diameter
  • OD: Outer diameter
Important: About DIN 3771 Size Naming

DIN 3771 uses metric measurements (millimeters), and it identifies sizes by the actual inner diameter and cross-section dimensions (for example, 20 x 2 mm). Other standard like AS568 use dash numbers (like AS568-210) that do not directly show the dimensions.

DIN 3771 Standard No. Range
(ID x CS)

CS (mm)

ID Range (mm)

OD Range (mm)

CS (inch)

ID Range (inch)

OD Range (inch)

1.8 X 1.8 ~ 17 X 1.8

1.80

1.80 ~ 17.00

5.40 ~ 20.60

0.071

0.071 ~ 0.669

0.213 ~ 0.811

14 X 2.65 ~ 38.7 X 2.65

2.65

14.00 ~ 38.70

19.30 ~ 44.00

0.104

0.551 ~ 1.524

0.760 ~ 1.732

18 X 3.55 ~ 200 X 3.55

3.55

18.00 ~ 200.00

25.10 ~ 207.10

0.140

0.709 ~ 7.874

0.988 ~ 8.154

40 X 5.3 ~ 400 X 5.3

5.30

40.00 ~ 400.00

50.60 ~ 410.60

0.209

1.575 ~ 15.748

1.992 ~ 16.165

206 X 7 ~ 670 X 7

7.00

206.00 ~ 670.00

220.00 ~ 684.00

0.276

8.110 ~ 26.378

8.661 ~ 26.929

What is DIN 3771 Standard?

DIN 3771 is a German standard for O-ring sizes, issued by the German Institute for Standards (Deutsches Institut für Normung). This standard identifies O-ring sizes by their inner diameter and cross-section (ID x C/S), and may include a letter indicating the quality level (N for normal quality, S for special quality) along with a code for the rubber material and hardness. DIN 3771 is widely used in German and European machinery, automotive, and industrial equipment where metric sizing is required.

ZSR Silicone manufactures silicone O-rings that fully match DIN 3771 standard sizes. If your equipment follows German or European design specifications and requires metric O-rings with defined quality grades, we can supply the correct DIN 3771 size in the silicone material that matches your application needs.

DIN 3771 vs. Other O-Ring Standards

Feature

DIN 3771

AS568 / BS 1806 / AN Standards

Origin

Germany (Deutsches Institut für Normung)

United States (SAE / MIL)

Sizing system

Metric (millimeters)

Imperial (inch-based)

Size identification

ID x C/S (inner diameter x cross-section)

Dash number system (e.g., AS568-210, AN6227-15)

Quality grades

N (normal) and S (special) quality levels

Not specified in the same way

Material/hardness coding

Included in the size designation

Separate from size designation

Regional use

Germany and Europe

Worldwide, especially Americas and Asia

  • Metric vs. Imperial: DIN 3771 uses metric measurements (millimeters), while AS568, BS 1806, and the AN standards use Imperial measurements (inches).
  • Size naming: DIN 3771 identifies sizes by the actual inner diameter and cross-section dimensions (for example, 20 x 2 mm). AS568 and related standards use dash numbers (like AS568-210) that do not directly show the dimensions.
  • Quality and material in the code: DIN 3771 includes quality level (N or S) and material/hardness information as part of the standard designation. Other standards typically separate size from material specifications.
  • Regional preference: DIN 3771 is the standard of choice for German and European equipment manufacturers. AS568 and its related standards (AN6227, AN6230, BS 1806) are more common in American, British, and Asian markets.