This EPDM O-ring is black in color, round in cross-section, has a durometer of 70A, and is designed for use in a wide variety of sealing applications. EPDM is acceptable for temperature applications between -67 degrees F (-55 degrees C) to 257 degrees F (125 degrees C). It is compatible for use with water and steam, silicone oil and grease, polar solvents (alcohols), acids, glycol-based brake fluids, ozone, and weathering. It is vulnerable to many oils, gasoline, and solvents. This material meets ASTM International standards. This EPDM O-ring has a shore durometer of 70A. Shore durometer is the hardness of a material, and its resistance to permanent indentation. A higher durometer value indicates greater resistance to indentation on a scale of 0 to 100, with 100 indicating no indentation. O-rings commonly provide a pressure and fluid seal between cylindrically shaped, overlapping mating surfaces and are commonly seen in engines, faucets, flanges, valves, and various cylinders. They are circular in shape, with a round cross section and a hole in the center, similar to a doughnut. O-rings are available in various sizes, and can be ordered based on required nominal inside diameter (ID), outer diameter (OD), and cross-sectional (CS) diameter. This EPDM O-ring meets standards defined by Aerospace Standard AS568A, which is the Aerospace Size Standard for O-rings.