British Standard O-Rings are very similar to Standard O-Rings in the fact that they are both standardized imperically. The British Standard however, incorporates some extended sizes in the 1/4" nominal cross section group for an even broader application range. British Standard O-Rings serve a variety of industries including aerospace, paint, food, and chemical transport.

This elastomer possesses mechanical properties similar to Viton®, with the exception of its slightly lower compression set resistance. It is more suitable for sensitive applications where lighter compressive forces are applied to energize the seal. This core has a Shore A hardness of 70 but it also offers a broader operating temperature range of -80°F to +500°F. (-62°C to +260°C). For more information, please see: Comparison Properties Chart, PTFE Encapsulated O-rings, Material Shelf Life, and O-ring Groove Design Chart.
Unit of Measure

Type

BS Standard O-Ring

Material

Silicone

Cross Section Width

0.210 in5.33 mm

Durometer

70

Inside Diameter

9.725 in247.02 mm

CSW Tolerance

0.005 in0.13 mm

BS Number

-376

Warning

Prop 65 Warning: This product may contain chemicals known to the State of California to cause cancer, and birth defects or other reproductive harm.

O-Ring Industries

O-rings are used in the military, automotive, aerospace and agriculture industries.