Fits Hope 6-bolt rotors, standard or floating R24 sensor is designed for Ebikes with a magnet 24mm from the axle center point R32 sensor is designed for bikes with a magnet 32mm from the axle center point Sensors are 3.5mm thick and require 4.5mm of clearance Not guaranteed to work with all Ebikes. Incompatible with Specialized Turbo Levo SL with 1.2 SL motor