Park Tool's Bottom Bracket Tapping & Facing Set is a precision tool system which provides a piloted means of tapping the threads in the bottom bracket shell of a frame. After tapping, the taps act as guides to keep the included facing cutter perfectly square with the axis of the bottom bracket for cleanup of the faces of the bottom bracket shell. The BTS-1 includes English taps, 1.370" x 24 TPI right hand thread for the adjustable cup, and 1.370" x 24 TPI left hand thread for the fixed cup. Italian thread taps, 36mm x 24 TPI right hand thread (Part #693) for the adjustable and fixed cups, are available as accessories.