Square O-Ring (ID:25 mm, CS:3 mm, OD:31 mm), 16PK The o ring is placed into a groove to secure them in place, and then compressed between two surfaces..
R-044 Square O-Ring (ID: 3 3/4", CS 1/16", OD 3 7/8"), 90PK The o ring is placed into a groove to secure them in place, and then compressed between two surfaces..