3/8" Impact Driver Impact Driver. Loosens hard-to-turn screws, bolts or nuts.. Handle design prevents possibility of hitting hand with hammer when striking impact driver.. Bit holder has 3/8 drive (No. 4608), 1/2 (No. 4607) drive, and 5/16 hex for Phillips and flat screwdriver bits.. Includes eight screwdriver bits: No. 2 Phillips bit, 1-3/8 long with 5/16 hex No. 2 Phillips bit, 3-1/8 long with 5/16 hex No. 3 Phillips bit, 1-3/8 long with 5/16 hex No. 3 Phillips bit, 3-1/8 long with 5/16 hex 5/16 wide x 1-3/8 long with 5/16 hex slotted bit 5/16 wide x 3-1/8 long with 5/16 hex slotted bit 3/8 wide x 1-3/8 long with 5/16 hex slotted bit 3/8 wide x 3-1/8 long with 5/16 hex slotted bit No. 4608 – 3/8 impact driver. 4608 No -