This item is a set of socket adaptors which is specially designed for screwdriver or electric screwdriver handle tools, which can be installed on the size of the original hexagonal to be converted to square head size. The set is for repair, car modification, wrench socket transformation. It can be used in automotive industry, household maintenance, manufacturing industry, construction. A great helper in your daily life. Feature - Color: Black - Material: vanadium - Size: 1/2 "to 3/8" - (12.7mm square hole to 9.53mm square head) 3/8 "to 1/4" - (9.53mm square hole to 6.35mm square head) 3/8 "to 1/2" - (9.53mm square hole to 12.7mm square head) 1/4 "to 3/8" - (6.35mm square hole to 9.53mm square head) - 4 pieces vanadium socket adapter and reducer set are use, high hardness, plated finish ensures performance. - For all four holes slot, sleeve mutual conversion, adjustable joints. - Allows you to match drive sizes for your sockets, ratchet handles, extension bars and other accessories. - Suitable for screwdriver or electric screwdriver handle tools, can be installed on the original hexagonal to be converted to square head. - Great for for repair, car modification, wrench socket transformation. Applicable to automotive industry, household maintenance, manufacturing industry, construction. Package list: 4 x Socket Adapter Converter