Value Collection ZMSCH70248 O-ring Dash 248 Nitrile 70A

Product Description

The VALUE COLLECTION ZMSCH70248 is a Dash 248 Buna-N O-ring designed for static and dynamic sealing applications across HVAC, plumbing, and fluid-handling systems. It measures 4.75 inches inside diameter and 5.0 inches outside diameter with a 0.125-inch round cross section. Manufactured from nitrile butadiene rubber (Buna-N) at a 70 Shore A hardness rating, this O-ring provides reliable sealing performance in systems that handle petroleum-based fluids, oils, and fuels. Installation is performed by HVAC technicians, plumbers, and mechanical service professionals working on pumps, valves, fittings, and compressor assemblies.

This O-ring is suited for residential and commercial applications involving petroleum products, hydraulic fluids, and similar media. The Dash 248 sizing is a standard AN/MS designation, making it a common replacement in a wide range of mechanical sealing points. It is appropriate for systems operating within a temperature range of -40 degrees F to 250 degrees F, covering most standard HVAC, refrigeration-adjacent, and fluid-system service environments. Each package contains 25 O-rings, with a minimum order quantity of 1.

Key Features

• Buna-N (nitrile butadiene rubber) construction offers excellent resistance to petroleum products, oils, and fuels
• 70 Shore A hardness provides a firm, reliable compression seal with good compression set resistance
• Round cross-section profile seats consistently in standard O-ring grooves
• Operating temperature range of -40 degrees F to 250 degrees F suits most HVAC and fluid-system service conditions
• Meets SAE and MIL-Spec standards
• Black color; package quantity of 25 per unit

Compatibility

Designed as a standard Dash 248 O-ring replacement for use with petroleum products and compatible media in mechanical sealing applications. Compatible materials include petroleum-based fluids and oils. Not recommended for exposure to ozone, direct sunlight during storage, or environments near motors or electrical equipment that may generate ozone.

Installation Notes

O-ring replacement is typically performed by licensed HVAC technicians or plumbers during valve, pump, or fitting service. Always depressurize and isolate the system before removing any sealing components. Lubricate the O-ring with a compatible fluid or O-ring lubricant before seating to prevent twisting or pinching during installation. Inspect the groove for scoring or corrosion that could compromise the seal before fitting the new O-ring.