The Kurt Kinetic Traxle Fine Thread (12mm Thru-Axle Fine Adaptor) is a precision-machined replacement axle for mountain bikes that easily adapts any 12mm thru-axle system to firmly lock into trainer cone cups. Specifically engineered to work on Kinetic trainers, the system is still adaptable enough to work with most other trainer brands making it a perfect solution for bike shop fitting stations and home-use alike. The Kinetic Adaptor comes in 3 thread pitches, coarse, medium and fine, to fit most bike brands. Unlike stock thru-axles, the Kinetic Adaptor has tapered heads that stand out just far enough from the bike frame to fit into the cone cups on a Kinetic trainer. This adaptor is for fine-threaded 12mm thru-axle systems including: Syntace X-12, DT SWISS (Tapered and Flat), Specialized thru-axles and Specialized 142+ System.