Stanley J4737 Proto 1/4-inch Drive Phillips Screwdriver Bit Socket - No. 1 Two piece design allows replacement of worn bits - Bit holders have a hex opening to hold the bit allowing the bit holder to take the full load of torque 1/4-inch Drive Phillips Screwdriver Bit Sockets No.1 Tip size 1-13/64-inch Overall length 0.04-lbs Weight.