ACM 70 Rubber O Ring Seals For Connector , Colored Orings Wear Resistant O-Ring Seals description : O-ring seals are the air and water tight connectors placed between two pieces of machinery. The round elastomeric O-ring sits in a gland, which is a groove in the metal part designed as a cavity to keep the O-ring in place. The seal compresses between the two machinery components and prevents the loss of fluid or gas. O-ring seals are components in pressure systems, in