3.5MM CS X 42MM ID BLACK BUNA 70D

Ordered as H3.5X42, this is a black Buna-N (Nitrile) 70 Shore A O-Ring built to an inside diameter of 42 mm (1.654 in), a cross section of 3.5 mm (0.138 in), and an outside diameter of 49 mm (1.93 in). The o-ring compresses into its gland to block fluid or gas migration across a joint.

This material stands up to petroleum-based oils, many alcohols, and hydraulic fluids. That behavior comes from the compound itself: Buna-N (Nitrile) delivers low compression set under sustained load, reliable performance in both static and dynamic service. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Applications involving ozone and direct sunlight or automotive brake fluid call for a different compound.

You will find this material specified across fluid power, general industrial maintenance, and agricultural equipment.

Reference part number H3.5X42 when ordering; the item is sold individually. Unit weight is approximately 1.6313 g. Application requirements vary, so validate compatibility with your process conditions prior to installation.