Split Lock Washer, Finish Black Oxide, Material Steel, For Screw Size 3/8 in, Inside Diameter 0.377 in, Outside Diameter 0.55 in, Maximum Thickness 0.125 in, Minimum Thickness 0.125 in, Color Black, Dimensional Standards ASME B18.21.1, Inside Diameter Tolerance +/-0.005 in, Made in North America No, Manufacturer Location Globally Sourced, Material Grade/Class Not Graded, Material Quality Standards ASTM A307A, SAE J429, Maximum Temperature 275 Degrees F, Minimum Temperature 10 Degrees F