Material: made of high-quality chrome vanadium steel, quantity: 8 pieces, 4x1/4’’, 2x3/8’’, 2x1/2’’ Suitable for all sockets, bit inserts, for direct drive via the drill chuck or using a 1/4" hexagon socket For all drills, cordless screwdrivers and hand screwdrivers etc. Ideal for quick tool changes with electric screwdrivers The hexagonal shank can also be used directly for a secure hold be clamped in a machine chuck The hexagonal shank is used in drills, square to accommodate 1/4’’, 3/8’’ and 1/2" nuts