An O-ring is a solid-rubber seal shaped like a doughnut or torus. When compressed between mating surfaces, an O-ring blocks the passage of liquids or gases. Two dimensions describe the size of an O-ring: its inside diameter (ID) and its cross-sectional diameter (CS).
Parco is your convenient source for quality O-rings. We offer O-rings that meet virtually every military and industrial specification in both standard and non-standard sizes. View Parco’s O-ring Size Chart for a list of all 369 standard O-ring sizes.