1.They are circular in shape, round in cross-section. For use across a wide temperature range from -4℉ (-20C) to 212℉ (100C). 2.Nitrile has good mechanical properties when compared with other elastomers and high wear resistance. Good resistance to many petroleum oils, greases, hydraulic fluids, mineral oil and grease. 3.This O-ring is made of black nitrile rubber, has a durometer of 70A, and is designed for use in a wide variety of sealing applications. 4.O-rings commonly provide a pressure and fluid seal between cylindrically shaped, overlapping mating surfaces and are commonly seen in , faucets, flanges, valves, and various cylinders. 5.Nitrile is vulnerable to acetone, ethers, esters, ozone, sunlight and weathering and should therefore not be used in ozone-generating electric motors, welding equipment, or in applications with exposure to UV light. Specifications: Outside Diameter: 6mm / 0.24-inch Inner Diameter: 2mm / 0.08-inch Cross-Section Diameter: 2mm / 0.08-inch Package Content: 50pcs x O-Ring