Professional tool for commercial or occasional use Manufactured from chrome vanadium steel for strength and durability 3/8" square drive so will fit any 3/8" drive ratchet / bars etc... Extra long bits (110mm total length) so ideal for access into those hard to reach awkward areas Metric sizes SET Includes; SIZES Includes sizes 3mm, 4mm, 5mm, 6mm, 7mm, 8mm and 10mm. Supplied in a blow molded case for easy storage and transportation