-340 BLACK BUNA 70D O-RING

Ordered as H70340, this is an AS568-340 black Buna-N (Nitrile) 70 Shore A O-Ring built to an inside diameter of 3.35 in (85.09 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 3.77 in (95.76 mm). The o-ring creates a positive seal at flange, piston and rod interfaces without added hardware.

This material stands up to petroleum-based oils, propane and butane, and water. That behavior comes from the compound itself: Buna-N (Nitrile) is valued for reliable performance in both static and dynamic service, low compression set under sustained load. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). Applications involving automotive brake fluid or ketones call for a different compound.

Maintenance and OEM teams specify it across construction equipment, automotive, and fluid power.

H70340 ships individually. Unit weight is approximately 7.63 g. As always, verify media compatibility and operating conditions against the requirements of your specific application.