Bike mechanics and serious cyclists, this crank bottom bracket adjuster is a must-have for proper DUB crank maintenance! Measuring 28.99mm in diameter, this alloy preload ring is specifically designed for adjusting bearing clearance on DUB cranks including XX1 Eagle and X01 Eagle models. Made from durable 7075 aluminum pretightening ring and aluminum alloy screw, this thing is built to last through repeated adjustments. Installation is straightforward - just use it to fine-tune your inner bearing clearance for that perfect, smooth rotation without any play. The purple color (and other available colors) lets you add a custom touch to your bike's look while serving an important function. It's compatible with most DUB cranks though note the flanged inner ring doesn't work with fat cranks. Weighing only about 45 grams, it's lightweight but seriously sturdy. Whether you're building up a new bike or doing routine maintenance on your current ride, having the right preload adjustment tool makes all the difference in crank performance and longevity. The simple design means easy installation and disassembly when needed. If you're tired of cranks that have too much play or drag, this adjuster helps you dial in that perfect bearing preload for optimal performance on every ride.