Value Collection ZMSCH70250 O-ring Dash 250 Buna-n

Product Description

The VALUE COLLECTION ZMSCH70250 is a Dash 250 Buna-N (Nitrile Butadiene Rubber) O-ring with a round cross section, designed for static and dynamic sealing applications across HVAC, plumbing, and fluid system service work. It measures 5 inches inside diameter, 5.25 inches outside diameter, and 0.125 inches thick. Rated at 70 Shore A hardness, this O-ring provides excellent resistance to petroleum-based fluids and compression set. It handles a working temperature range of -40 degrees F to 250 degrees F, making it suitable for a broad range of service environments encountered in trade work.

This O-ring is used in residential and commercial applications wherever a Dash 250 size is specified. Typical install scenarios include pump seals, valve bodies, pipe fittings, hydraulic connections, and fluid handling components that contact petroleum products or mineral oils. The Buna-N elastomer is the most widely used O-ring material in the trade due to its balance of chemical resistance, tear resistance, and abrasion resistance. Package quantity is 10 rings per package, with a minimum order of 1 package.

Key Features

• Buna-N (Nitrile Butadiene Rubber) elastomer — the most widely used O-ring material in fluid sealing applications
• Excellent resistance to petroleum products, mineral oils, and hydraulic fluids
• Round cross section with 70 Shore A hardness rating for reliable compression set performance
• Wide temperature range: -40 degrees F to 250 degrees F
• Meets SAE and MIL-Spec standards
• Sold in packs of 10; minimum order quantity of 1 pack

Compatibility

Designed as a standard Dash 250 O-ring replacement compatible with petroleum-product and mineral-oil fluid systems. Not recommended for use with ozone-generating environments, direct sunlight exposure, or applications requiring FDA-approved materials.

Installation Notes

Installation is typically performed by licensed plumbers, HVAC technicians, or fluid system mechanics as part of valve, pump, or fitting service. Always depressurize and drain the system before replacing O-rings. Inspect the seating groove for damage or debris before installing the new O-ring. Avoid twisting or overstretching the O-ring during installation; use a compatible petroleum-based lubricant to ease seating where the application permits.