Park tool bb adjustable cup wrench hcw 11as a manufacturer of bicycle specific tools since 1963 you can safely rely on park tools many years of experience the worlds largest bike tool manufacturer is the first choice of professional and home bicycle mechanics around the world the hcw 11 fits slotted bottom bracket adjusting cups and cups with raised 16mm wrench flats these are common on older english bicycles and less expensive bicycles the opposite end has two ears that are 23mm wide