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Buna-N Dished Back-ups

Buna-N 90 Contoured Back-Up Rings

Contoured Back-Ups are routinely produced in a 90 durometer Nitrile - Buna-N. This provides sufficient elasticity to permit stretching over the major diameter of a piston and then snapping back into the gland groove cut into the piston. 90 durometer has sufficient hardness to resist extrusion of the softer elastomeric O-Ring performing the actual sealing function against the high pressure liquid or gas.
- 000 Series O-rings 0.070" ±0.003" - .045" Thick
- 100 Series O-rings 0.103" ±0.003" - .045" Thick
- 200 Series O-rings 0.139" ±0.004" - .040" Thick
- 300 Series O-rings 0.210" ±0.005" - .060" Thick
- 400 Series O-rings 0.275" ±0.006" - .096" Thick>
NOTE: Sizes (Dash No.) corresponds to O-ring numbers. Link to complete size chart: Rubber Contoured Back-Up Ring Size Chart

Operating Temperature -40 to 212°F

We started as a simple online company taking care of a precious few people. Our circle of business friends has grown over the years and taking care of them is more satisfying than ever. We take care of our customers' Standard O-Rings, Metric O-Rings, Vulcanized O-Rings, and Custom O-Rings. Just place your O-Ring order online and we will take care of you too.

We are a family owned and operated Distributor and Manufacturer of O-Rings, O-Ring Kits, OSK™ O-Ring Service Kits, Hydraulic Seals, Adhesives, Lubricants, Braided Packings, Coatings, O-Ring Cord, Lathe Cut, Oil and Shaft Seals, Gaskets, Retaining Rings, Molded Packings, Seals, and Molded Rubber Products.

We serve many industries, including manufacturing, chemical processing, defense, power generation, agricultural, water treatment and filtration, hydraulics, fluid power, heavy truck, automotive, aerospace, oil and gas, medical and life sciences, food and beverage, electronics and industrial controls, refineries, and supply chain suppliers. Each industry and each customer have unique requirements that make them special. We love sharing customer stories and applications at our weekly store meeting.