Washer Assortment, Finish Plain, Includes (20) Washers 00, (20) Washers 000, (20) Washers 1/2, (20) Washers 3/8, (20) Washers 3/8L, (20) Washers 3/8M, (40) Washers 0, (40) Washers 1/4, (40) Washers 1/4L, Largest Outside Diameter 3/4 in, Largest Screw Size 3/16 in, Material PTFE, Number of Sizes Included 9, Number of Washers Included 240, Resistance Properties High Mineral Content Water , High Temperature , Screw Sizes 3/16 in, Smallest Outside Diameter 15/32 in