Shimano BB-6207 is a bottom bracket assembly designed for use with the Shimano FC-6207 front chainwheel. It features a sealed mechanism to prevent mud entry, a short pin to assist with chain replacement, and a safety crank concept for comfortable riding. The BB-6207 is compatible with 1/2" X 3/32" chains and has a gear setting pitch diameter of 130 mm (LD pitch). It includes crank fixing bolts, ball retainers, and a lock ring for easy assembly. The assembly process involves greasing the cup threads, installing the ball retainers, and adjusting the left-hand cone to eliminate play.