This kit includes end caps and a quick-release skewer, allowing you to convert your thru-axle 6-bolt E-sync, Neo, or Neo Ultimate rear hub to a 10x135mm quick-release system. Compatible with 6-bolt E-sync, Neo, and Neo Ultimate 12x142mm rear hubs. Compatible with frames with traditional, quick-release-compatible dropouts. Not compatible with any 148mm hub. Not compatible with Centerlock hubs. Not compatible with frames designed for thru-axles. Not compatible with M-pulse hubs.