For use with 2000+ Hayes 74mm eye-to-eye calipers (adapters/calipers for 22mm mounts are no longer available) - (IS) International Standard 51mm tabs; (QR) Quick Release; (TA) thru-axle - Note: Fox-36/40 (thru-axle), Rock Shox Pike (Maxle), and Psylo (Tullio) axle forks use IS-QR adapters