- Fits Hope 6-bolt rotors, standard or floating - R24 sensor is designed for E-bikes 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 E-bikes. Incompatible with Specialized Turbo Levo SL with 1.2 SL motor