Value Collection ZMSCH90240 O-ring 3.75 in Id Buna-n Dash 240

Product Description

The VALUE COLLECTION ZMSCH90240 is a Dash 240 Buna-N O-ring sized at 3.75 inches inside diameter, 4 inches outside diameter, and 0.125 inches thick. Made from nitrile butadiene rubber with a 90 durometer (extra hard) hardness rating, this O-ring delivers excellent resistance to petroleum-based fluids, strong compression set performance, and solid tear and abrasion resistance. It carries a working temperature range of -40 to 250 degrees F. HVAC technicians, plumbers, and hydraulic system mechanics install this type of seal in fluid handling assemblies, valve bodies, pump housings, and pipe connections where petroleum-based media are present.

This O-ring is suited for residential and commercial applications involving petroleum products, hydraulic oils, fuels, and general fluid sealing. The Dash 240 size is a standard AN/SAE designation, making it a common replacement in industrial equipment, HVAC refrigerant service fittings compatible with this seal profile, pump assemblies, and fluid control valves. It is sold in a package quantity of 50 units, making it practical for service shops that replace O-rings during routine maintenance or rebuild operations.

Key Features

• Buna-N (nitrile butadiene rubber) material with excellent petroleum product resistance
• 90 durometer extra hard hardness rating for high-pressure sealing applications
• Wide temperature range: -40 to 250 degrees F
• Standard Dash 240 cross-section designation per SAE and MIL-Spec standards
• Round cross-section, black color, 0.125 inches thick
• Package quantity of 50 units for shop stock or bulk replacement work

Compatibility

Compatible with petroleum products and petroleum-based hydraulic fluids. Meets SAE and MIL-Spec standards for Dash 240 O-ring sizing. Not recommended for exposure to ozone, direct sunlight during storage, or proximity to motors and electrical equipment that may generate ozone.

Installation Notes

O-ring replacement is performed by licensed HVAC technicians, plumbers, and hydraulic system mechanics depending on the application. Always depressurize the system and shut off all fluid supply before removing the old seal. Inspect the O-ring groove for damage, burrs, or debris before seating the new ring, and apply a compatible lubricant to ease installation and reduce the risk of seal damage. Follow applicable codes such as the IPC or IFGC when installing seals in gas or plumbing assemblies.