*4129-366Y MINNESOTA RUBBER QUAD RING

The HQ4129 is an AS568-129 black Buna-N (Nitrile) 70 Shore A Quad-Ring measuring an inside diameter of 1.549 in (39.34 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 1.755 in (44.58 mm). This quad-ring seats in a standard o-ring gland while offering improved dynamic performance.

This material stands up to many alcohols, propane and butane, and petroleum-based oils. That behavior comes from the compound itself: Buna-N (Nitrile) offers strong abrasion and tear resistance, the most widely specified general-purpose sealing elastomer. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). Applications involving polar solvents or ketones call for a different compound. The profile itself contributes resistance to the spiral twisting that defeats round-section rings and two sealing bands per contact face rather than one.

Maintenance and OEM teams specify it across fluid power, hydraulic and pneumatic systems, and agricultural equipment.

HQ4129 ships individually. Application requirements vary, so validate compatibility with your process conditions prior to installation. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.