Bottom bracket conversion kit for 3 piece square taper spindle cranks made by YST. Convert your one piece crank to three piece with this spindle/bottom bracket. Spindle is for JIS (Japanese) square taper cranks - this will NOT fit Campagnolo square taper, Sugino Super Mighty or Haro Group 1 cranks from the mid-80's. Cranks we do know that this will fit are Sugino Maxy Cross, Suntour VX, and Takagi Tourney. Size: American Bottom Bracket (51.5mm diameter cups, 130mm long spindle) SEALED MECHANISM (which means it has a plastic cover that goes between the cone and the bearing that keeps dirt/water out). All parts shown are included.