The SH70038 is an AS568-038 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring measuring an inside diameter of 2.614 in (66.4 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 2.754 in (69.95 mm). This square-cut ring seals with a broad flat contact band instead of the line contact of a round-section ring.
As a material, Buna-N (Nitrile) is known for the most widely specified general-purpose sealing elastomer, strong abrasion and tear resistance. The compound resists petroleum-based oils, water, and hydraulic fluids. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). Applications involving automotive brake fluid or polar solvents call for a different compound. The profile itself contributes a rectangular section that will not roll in the groove and greater resistance to extrusion than a round section of the same size. Note that a square section is less suited to high-speed rotary service, where the larger contact area raises friction and heat.
Maintenance and OEM teams specify it across general industrial maintenance, hydraulic and pneumatic systems, and construction equipment.
Reference part number SH70038 when ordering; the item is sold individually. Unit weight is approximately 0.77 g. As always, verify media compatibility and operating conditions against the requirements of your specific application.
description 568-038 BUNA 70 SQUARE CUT RINGS
Actual_CS 0.07 inch (1.78 mm)
Actual_ID 2.614 inch (66.4 mm)
Actual_OD 2.754 inch (69.95 mm)
ProductCode Description O-Rings - Square/Quad - Commodity