Professional tool for commercial or occasional use. Double deep (approx. 60mm total length) over standard shallow sockets. Single Hex design for strength and to help prevent rounding of nuts. 3/8" square drive. Manufactured from chrome vanadium steel for strength and durability SET Includes; SIZES 8mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm & 19mm Includes socket rail for storage and transportation.