The 10 pieces 3/8" drive low profile nano impact socket set is constructed from high-strength chrome molybdenum steel , with a protective black phosphate coating. Constructed from heat-treated, impact Chrome Molybdenum Steel, with a protective black phosphate coating. Set Includes: 1/4", 9/32", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4". These low profile nano sockets are lower than standard shallow sockets, making them easy to use even in tight spaces. High contrast and specific size marking for identification. It helps you select the size easier. It comes with a sturdy and convenient storage case. Keep each piece in the proper position. All products meet or exceed ANSI performance standards.