3.55MM CS X 128MM ID BLACK BUNA 70D

APG stocks the H3.55X128, a black Buna-N (Nitrile) 70 Shore A O-Ring supplied with an inside diameter of 128 mm (5.039 in), a cross section of 3.55 mm (0.14 in), and an outside diameter of 135.1 mm (5.32 in). An o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load.

The compound resists propane and butane, greases and lubricants, and petroleum-based oils. Buna-N (Nitrile) is widely chosen for low compression set under sustained load and the most widely specified general-purpose sealing elastomer. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where ketones or automotive brake fluid are present.

Common environments for this compound include fluid power, hydraulic and pneumatic systems, and construction equipment.

Stocked as H3.55X128 and sold individually. Unit weight is approximately 5.2085 g. Application requirements vary, so validate compatibility with your process conditions prior to installation. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.