PARK TOOL HCW-4 BOTTOM BRACKET TOOL The Park Tools HCW-4 Crank and Bottom Bracket Wrench feature Park Tools proven "Y" head design with a 36mm box-end and bottom bracket pin spanner. Features Center to center measurement between pins is 29mm. Pin diameter is nominally 2. 3mm Manufacturer's Part No: HCW-4 UPC: 763477004031 | Park Tool | Hcw-4 Bottom Bracket Tool 36Mm Box End/bottom Bracket Pin Spanner