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. Neoprene is also known as Chloroprene.

Neoprene resists fats, oils and petroleum products. Stands up well in sunlight. Low flammability - burns when exposed to flames, but self-extinguishes when flame is removed. Generally good ozone, aging and chemical resistance. It has good mechanical properties over a wide temperature range.

Unit of Measure

Inside Diamter

N/A 2.875 in73.03 mm

Cross Section Width

N/A 0.139 in3.53 mm


N/A 70

CSW Tolerance

N/A 0.004 in0.10 mm

BS Number

N/A -845


N/A BS Standard O-Ring


N/A Neoprene


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

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