Includes spring lock washers: 50 piece each: #6, #8, #10, 40 piece 1/4-Inch, 30 piece 5/16-Inch, 20 piece 3/8-Inch * External tooth lock washers: 50 piece each: #6, #8, #10, 40 piece 1/4-Inch, 30 piece 5/16-Inch, 20 piece 3/8-Inch * Internal tooth lock washers: 50 piece each: #6, #8, #10, 40 piece 1/4-Inch, 30 piece 5/16-Inch, 20 piece 3/8-Inch * Storage case keeps washers clean and organized