Value Collection ZMSCH70311 Dash 311 Nbr O-ring 50 Pack

Product Description

The VALUE COLLECTION ZMSCH70311 is a Dash 311 Buna-N O-ring with a round cross section, sold in a package of 50 pieces. Measuring 0.563 inches inside diameter, 0.938 inches outside diameter, and 0.1875 inches thick, this O-ring is molded from nitrile butadiene rubber (NBR) with a Shore A hardness of 70. It is rated for service from -40 degrees F to 250 degrees F and offers reliable sealing performance in systems handling petroleum-based fluids. Licensed plumbers, HVAC technicians, and maintenance professionals commonly stock Dash 311 O-rings for routine service work across hydraulic, pneumatic, and fluid-handling assemblies.

This O-ring is suited for use in residential and commercial applications involving petroleum products, hydraulic fluids, and oils. The Buna-N compound delivers strong compression set resistance along with tear and abrasion resistance, making it a dependable choice for dynamic and static sealing applications. It complies with SAE and MIL-Spec standards, supporting use in both general trade and specification-driven maintenance environments. The 50-piece package quantity supports service shops and field technicians who carry inventory for common seal sizes.

Key Features

• Buna-N (NBR) compound — the most widely used O-ring elastomer for petroleum-fluid compatibility
• Dash 311 standard sizing: 0.563 inches ID, 0.938 inches OD, 0.1875 inches thick
• Operating range of -40 degrees F to 250 degrees F
• Shore A hardness rating of 70 for a hard, durable cross section
• Meets SAE and MIL-Spec standards
• Round cross-section profile for consistent groove seating

Compatibility

Compatible with petroleum products and petroleum-based hydraulic fluids. Not recommended for use with ozone-generating environments, direct sunlight exposure, or near electrical motors. Not FDA approved. Designed as a standard Dash 311 replacement O-ring for any application requiring this cross-section and nominal sizing.

Installation Notes

Install this O-ring only after depressurizing and draining the system being serviced. Lightly lubricate the O-ring with a compatible fluid or O-ring lubricant before seating to reduce the risk of tearing during installation. Avoid rolling or twisting the O-ring into the groove. Plumbers and HVAC technicians should follow applicable system-specific service procedures and local codes when replacing seals in pressurized lines.