This Garmin Tacx E-Thru 12mm axle with 1.75mm standard course thread replaces the standard trainer axle and accommodates mountain bikes with Maxle axle 135 x 12, 142 x 12, 150 x 12mm, and Trek ABP 142 x 12 rear axles, and an external frame width of 179.5mm max. Please determine your bikes rear axle thread, as Garmin offers various Tacx trainer axles with thread ranging from 1mm fine to 1.75mm standard course. Suitable for the following Garmin Tacx trainers with rear wheel drive : Genius IRONMAN Bushido Vortex Flow Satori Booster Blue Motion Blue Matic Blue Twist Specifications: Axle Size: 135 x 12mm, 142 x 12mm, 150 x 12mm Thread Size: 12 x 1.75mm Length: 179.5mm