Value Collection ZMSCH70256 O-ring Nitrile Dash 256

Product Description

The VALUE COLLECTION ZMSCH70256 is a Dash 256 Nitrile Butadiene Rubber (Buna-N) O-ring with a 5.75-inch inside diameter, 6-inch outside diameter, and 0.125-inch cross-section thickness. It features a round cross-section profile and a Shore A hardness of 70, rated Hard. Buna-N is the most widely used O-ring elastomer in industrial and mechanical applications, offering excellent resistance to petroleum-based fluids along with strong compression set, tear resistance, and abrasion resistance. Licensed HVAC technicians, plumbers, and mechanical contractors specify this material for sealing applications involving oils, fuels, and hydraulic fluids.

This O-ring is suited for use in residential and commercial HVAC systems, plumbing assemblies, hydraulic circuits, and fluid-handling equipment where petroleum-product exposure is present. Its operating temperature range spans -40 degrees F to 250 degrees F, making it appropriate for a broad range of service environments. The Dash 256 designation follows standard AS568 sizing, allowing straightforward cross-referencing to OEM specifications. It ships in a package quantity of 10 units.

Key Features

• Buna-N (Nitrile Butadiene Rubber) material with excellent petroleum-product resistance
• 5.75-inch inside diameter and 6-inch outside diameter, 0.125-inch cross-section thickness
• Shore A hardness of 70, rated Hard for reliable compression sealing
• Operating range: -40 degrees F to 250 degrees F
• Round cross-section profile meets SAE and MIL-Spec standards
• Standard Dash 256 sizing for easy OEM cross-reference

Compatibility

Compatible with petroleum products including oils, fuels, and hydraulic fluids. Designed as a standard Dash 256 AS568-size O-ring replacement for use in HVAC, plumbing, hydraulic, and general mechanical sealing applications. Not FDA approved. Should not be stored in direct sunlight or near motors or other electrical equipment that may generate ozone.

Installation Notes

Installation is typically performed by licensed HVAC technicians, plumbers, or mechanical service professionals. Always depressurize and de-energize the system before removing or replacing any O-ring seal. Ensure the seating groove is clean and free of debris before installing the new O-ring. Lightly lubricating the O-ring with a compatible fluid during installation helps prevent rolling or tearing during assembly.