R-333 Square O-Ring (ID: 2 1/2", CS 3/16", OD 2 7/8"), 120PK The o ring is placed into a groove to secure them in place, and then compressed between two surfaces..
R-427 Square O-Ring (ID: 4 3/4", CS 1/4", OD 5 1/4"), 16PK The o ring is placed into a groove to secure them in place, and then compressed between two surfaces..
.R-249 Square O-Ring (ID: 4 7/8", CS 1/8", OD 5 1/8"), 2PK The o ring is placed into a groove to secure them in place, and then compressed between two surfaces.