Includes spring lock washers: 50 pieces each: #6, #8, #10, 40 pieces ¼”, 30 pieces 5/16”, 20 pieces 3/8”; external tooth lock washers: 50 pieces each: #6, #8, #10, 40 pieces ¼”, 30 pieces 5/16”, 20 pieces 3/8”; internal tooth lock washers: 50 pieces each: #6, #8, #10, 40 pieces ¼”, 30 pieces 5/16”, 20 pieces 3/8”. Storage case keeps washers clean and organized.