The Wheels Manufacturing BSA 30 bottom bracket threaded to 30mm is their solution to running a 30mm spindle crankset in a BSA (English) threaded frame. This bottom bracket features high quality aluminum cups and fully serviceable bearings. Enduro ABEC-3 sealed bearings are replaceable. Grade 10 chromium steel balls, 52100 High Carbon Chromium Alloy Races provide smooth crank rotation. Machined aluminum cups with durable anodized finish. Allows for the use of 30mm spindle crankset with English (BSA) threaded bottom bracket shells. For use with 30mm diameter cranks with an overall spindle length of at least 104mm when used in a 68mm wide BB shell. Will not work with standard BB30 cranksets, please measure your BB30 crank spindle length. Compatible with frames that have 68-73mm English bottom bracket shells . Item Specifications: Bottom Bracket Shell I.D.: 1.37, BB/Frame Interface: English, BB Shell Width (mm): 68, BB Shell Width (mm): 73, Weight: 102, Spindle Interface Type: RaceFace Cinch 30mm, Defined Color: Orange,