The DT Swiss EXP 54 Tooth Upgrade Kit features ratchet grease, two ratchets, and two springs to maintain or upgrade your EXP hub wheels. This is the 54T version which is only compatible with EXP Hubs made after 2021. A separate special tool is required to remove the inboard drive ring. This kit helps you increase the speed of gearbox engagement for faster power transfer. The DT Swiss Upgrade Kit is a simple way to get the most out of your hub.