Fleck (13577-01) O-ring, -226, 560CD - 2-7/8" ID, 3-1/4" OD, 3/16" CS -336 Additional Details ------------------------------ Bullet point: Made of silicone for use with a variety of chemicals and fluids Round in cross-section to provide a seal between cylindrical overlapping surfaces Durometer (hardness) of 70A for resistance to penetration Meets standards defined by Aerospace Standard AS568A