The H70427 is an AS568-427 black Buna-N (Nitrile) 70 Shore A O-Ring supplied with an inside diameter of 4.725 in (120.02 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 5.275 in (133.99 mm). This o-ring creates a positive seal at flange, piston and rod interfaces without added hardware.
As a material, Buna-N (Nitrile) is specified for low compression set under sustained load, strong abrasion and tear resistance. The compound resists greases and lubricants, petroleum-based oils, and propane and butane. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. Applications involving ozone and direct sunlight or automotive brake fluid call for a different compound.
Maintenance and OEM teams specify it across fluid power, construction equipment, and hydraulic and pneumatic systems.
Order part number H70427, sold individually. Unit weight is approximately 18.7 g and nominal inside diameter is listed as 4 3/4 inch. Check the compound against your process media, pressure and temperature before committing to a design. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.
Description -427 BLACK BUNA 70D O-RING
Actual Cross Section 0.275 inch (6.99 mm)
Actual Inside Diameter 4.725 inch (120.02 mm)
Actual Outside Diameter 5.275 inch (133.99 mm)
Measurement System Imperial
Product Category O-Rings - Bulk - Commodity