Performance Tool W1389 Bit Set, 100-Piece Use with screwdrivers, electric drills or socket wrenches Includes bit adapters, magnetic bit holder and many types of bits Includes most bits you'll need around the house and garage Includes bit adapters, magnetic bit holder, "Y" style bits, couplers, Phillips, pozi, square, slotted, spanner, star, torque, tamper resistant star, hex triwing, clutch head and spline bits.