Value Collection ZMSCHB90213 O-ring Backup Ring Nbr Dash 8-213

Product Description

The VALUE COLLECTION ZMSCHB90213 is a rectangular-cross-section backup O-ring made from Nitrile Butadiene Rubber (NBR). It measures 0.955 inches inside diameter, 1.192 inches outside diameter, and 0.0468 inches thick. The 90-durometer extra-hard rating classifies this as a backup ring, designed to prevent extrusion of a primary O-ring under pressure. The Dash 8-213 designation identifies the size within the standard O-ring sizing system. Rated for service from -40 degrees F to 250 degrees F, it suits a wide range of fluid-sealing applications in HVAC, plumbing, and hydraulic assemblies. Licensed technicians and journeyman plumbers are the typical installers.

This backup ring is used in hydraulic, pneumatic, and fluid-handling systems where a primary O-ring requires anti-extrusion support in high-pressure or dynamic-service grooves. The NBR compound offers solid resistance to petroleum-based fluids, making it a common choice in refrigerant service valves, hydraulic cylinder assemblies, pump housings, and plumbing fittings. The rectangular cross section seats flush against the primary seal to prevent gap extrusion under pressure cycling. Each package contains 50 pieces, making it practical for bench-stock or service-van inventory replenishment.

Key Features

• Rectangular cross section provides anti-extrusion support for primary O-rings under pressure
• 90-durometer extra-hard NBR compound resists petroleum-based fluids and hydraulic media
• Operating temperature range of -40 degrees F to 250 degrees F suits HVAC and fluid-handling service
• Dash 8-213 sizing conforms to standard O-ring dash-number identification
• Sold in a 50-piece package, suitable for shop stock or service inventory

Compatibility

Designed as a standard Dash 8-213 backup ring for use with primary O-rings in grooves requiring anti-extrusion support across hydraulic, pneumatic, plumbing, and HVAC fluid-sealing applications.

Installation Notes

Installation should be performed by a licensed plumber, HVAC technician, or hydraulic systems technician following applicable codes. Depressurize and isolate the system completely before disassembling any seal gland or fitting. Inspect the groove for burrs or damage before seating the backup ring, and ensure the primary O-ring is installed on the high-pressure side of the backup ring. Avoid rolling or twisting the ring during installation to prevent distortion of the rectangular cross section.