This quad-ring is supplied in AS568-109 black Buna-N (Nitrile) 70 Shore A quad profile with an inside diameter of 0.299 in (7.59 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 0.505 in (12.83 mm), catalogued under part number HQ4109. It seats in a standard o-ring gland while offering improved dynamic performance.
This material stands up to hydraulic fluids, petroleum-based oils, and water. That behavior comes from the compound itself: Buna-N (Nitrile) delivers reliable performance in both static and dynamic service, an economical choice for high-volume maintenance programs. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Applications involving ozone and direct sunlight or polar solvents call for a different compound.
Maintenance and OEM teams specify it across hydraulic and pneumatic systems, construction equipment, and automotive.
HQ4109 ships individually. Nominal inside diameter is listed as 5/16 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.
description 4109-366Y MINNESOTA RUBBER QUAD RING
Actual_ID 0.299 inch (7.59 mm)
Actual_OD 0.505 inch (12.83 mm)
Actual_CS 0.103 inch (2.62 mm)
ProductCode Description O-Rings - Square/Quad - Premium