.R-256 Square O-Ring (ID: 5 3/4", CS 1/8", OD 6"), 48PK The o ring is placed into a groove to secure them in place, and then compressed between two surfaces.
R-331 Square O-Ring (ID: 2 1/4", CS 3/16", OD 2 5/8"), 24PK The o ring is placed into a groove to secure them in place, and then compressed between two surfaces..