TRP DISC ROTOR TRP-42 180mm 6b 2pc BLACK E-BIKE w/BOLTS2 piece, 2. 3mm thick rotors specifically for E Bike use with TRP G Spec E MTB calipers 2. 3mm thick stainless steel design dissipates heat and resists warping under heavy loads Six laser cut grooves allow water, mud, and other debris trapped between the pad and rotor to escape during braking **Not compatible with standard calipers**