An adapter body is configured to be attached to a vehicle body in each of a first orientation in which a caliper body is coupled to the vehicle body via the adapter body in a first position corresponding to a first disc brake rotor having a first outer diameter, and a second orientation in which the caliper body is coupled to the vehicle body via the adapter body in a second position corresponding to a second disc brake rotor having a second outer diameter different from the first outer diameter. The indicator is configured to indicate an correspondence between an orientation of the adapter body and at least one of the first disc brake rotor and the second disc brake rotor.