Superior Electric M1670-T Aftermarket Replacement Chuck Assembly Service Kit Replaces Milwaukee 48-66-1381 Replaces: 48-66-3280 Chuck Key Replaces: 48-66-1381 1/2 inch Reversing Thread Chuck Replaces: 06-75-3155 1/4 inch - 20 x 1 inch Socket HD Screw L.H Thread Replaces: 45-88-0330 Chuck Spacer Washer