Ordered as H70431, this is an AS568-431 black Buna-N (Nitrile) 70 Shore A O-Ring built to an inside diameter of 5.225 in (132.72 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 5.775 in (146.69 mm). The o-ring delivers dependable bidirectional sealing in a compact groove envelope.
The compound resists propane and butane, greases and lubricants, and petroleum-based oils. Buna-N (Nitrile) delivers low compression set under sustained load, strong abrasion and tear resistance. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C).
Maintenance and OEM teams specify it across general industrial maintenance, automotive, and fluid power.
H70431 ships individually. Unit weight is approximately 20.64 g and nominal inside diameter is listed as 5 1/4 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.
Description -431 BLACK BUNA 70D O-RING
Actual Cross Section 0.275 inch (6.99 mm)
Actual Inside Diameter 5.225 inch (132.72 mm)
Actual Outside Diameter 5.775 inch (146.69 mm)
Measurement System Imperial
Product Category O-Rings - Bulk - Commodity