- Prevents side-to-side play in thru-spindle bottom brackets to ensure bearings do not wear out prematurely - Replaces stock plastic preload rings on bikes with SRAM 30mm spindle cranks, Race Face 30mm spindle cranks, Easton 30mm spindle cranks, and SRAM DUB 28.99 spindles - Super durable, Precision CNC Machined 7075 piece of hardware