A multi-functional screwdriver including a shaft forming a pair of coplanar bends rotatably mounted to a handle having therein a compartment for storing a plurality of bits is disclosed. To prevent rotation of the shaft within the handle, a locking device is provided which includes a locking member and a collar assembly. The collar assembly includes a lever collar attached to the handle, a locking clamp collar attached to an upper section of the shaft, and an insulator collar for rotatably connecting the lever collar and locking clamp collar. The locking member pivotally attaches to the lever collar and is removably inserted into a depression in the locking clamp collar to prevent the shaft from rotating within the handle.