Industrial-grade O-rings are essential sealing components used across a remarkably wide range of applications—from hydraulic and pneumatic systems to aerospace assemblies, automotive engines, and industrial machinery. At Mutual Screw & Supply, we know that selecting the right O-ring for your application means getting the material, size, and durometer just right. That's why we have put together reference guides covering the various O-ring materials and standards currently represented in our inventory—just click the relevant links posted on this page. If you already know what you need, you can dive straight into our selection of Buna-N, Neoprene, EPDM, Silicone, and Viton O-rings listed in this section.