The Xcelite 10M Magnetic Nut Driver with Fixed Handle, 5/16 in. x 3 in., provides convenience to assembly and service operations involving hex fasteners. It is equipped with an Alnico permanent magnet, which is inside the socket. The magnet firmly holds fasteners, allowing for easy, one-handed driving, retrieving or removal. The socket has been specially treated and hardened for use with self-tapping screws. The comfortable contoured handle provides enough torque for one-handed driving.