The H4.5X66 is a black Buna-N (Nitrile) 70 Shore A O-Ring built to an inside diameter of 66 mm (2.598 in), a cross section of 4.5 mm (0.177 in), and an outside diameter of 75 mm (2.95 in). This o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load.
The material holds up against water, greases and lubricants, and petroleum-based oils. That behavior comes from the compound itself: Buna-N (Nitrile) is specified for strong abrasion and tear resistance, low compression set under sustained load. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service.
It sees regular use in general industrial maintenance, construction equipment, and agricultural equipment.
Reference part number H4.5X66 when ordering; the item is sold individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. For a size or compound outside the standard catalog, APG can quote from a print or sample.
Description 4.5MM CS X 66MM ID BLACK BUNA 70D
Actual Outside Diameter 75 mm (2.95 inch)
Actual Cross Section 4.5 mm (0.177 inch)
Actual Inside Diameter 66 mm (2.598 inch)
Measurement System Metric
Product Category O-Rings - Metric - Commodity