Value Collection ZMSCH70204 O-ring Dash 204 Nitrile Buna-n

Product Description

The VALUE COLLECTION ZMSCH70204 is a Dash 204 Buna-N (Nitrile Butadiene Rubber) O-ring with a round cross section, sized at 0.375 inches inside diameter, 0.625 inches outside diameter, and 0.125 inches thick. Rated at 70 Shore hardness, this O-ring is designed for use in fluid and gas sealing applications across HVAC, plumbing, refrigeration, and general mechanical systems. Its Buna-N compound is the most widely used O-ring elastomer in the trade, offering reliable performance with petroleum-based fluids, hydraulic oils, and fuels. It is installed by HVAC technicians, plumbers, and mechanical contractors in both residential and commercial applications.

This O-ring is suited for sealing applications involving petroleum products, hydraulic systems, and fuel lines. It performs across a wide service temperature range of -40 degrees F to 250 degrees F, making it appropriate for typical HVAC refrigerant line fittings, valve stems, compressor ports, and plumbing connections where a Dash 204 cross-section profile is specified. It is not recommended for exposure to ozone-generating equipment, direct sunlight storage, or applications requiring FDA-compliant materials.

Key Features

• Buna-N (Nitrile Butadiene Rubber) compound with excellent resistance to petroleum products and hydraulic fluids
• 70 Shore hardness rating provides firm sealing compression without excessive deformation
• Service temperature range from -40 degrees F to 250 degrees F
• Round cross-section profile to Dash 204 standard dimensions
• Meets SAE and MIL-Spec standards
• Good tear and abrasion resistance for repeated installation cycles

Compatibility

Compatible with petroleum products, hydraulic oils, and fuel-based media. Meets SAE and MIL-Spec standards for Dash 204 O-ring profiles. Not FDA approved; not suitable for food-contact or potable water applications where FDA-compliant elastomers are required.

Installation Notes

Installation should be performed by a qualified HVAC technician, plumber, or mechanical contractor. Always depressurize and isolate the system before removing or replacing any O-ring seal. Lubricate the O-ring with a compatible fluid or O-ring lubricant prior to installation to prevent tearing or twisting during assembly. Do not store O-rings near motors, electrical equipment, or in direct sunlight, as ozone and UV exposure degrade Buna-N compound over time.