A floating caliper, common on production vehicles, has a piston or pistons only on the inboard side of the caliper. The floating caliper is mounted on pins or slides so that when the piston extends and presses the inboard pad against the rotor, the whole body of the caliper slides on its pins or guides in the opposite direction, bringing the outboard pad into contact with the rotor.
Floating calipers cool better as the fluid and piston are only on the inboard side of the rotor.
Floating calipers have fewer moving parts and seals to leak or wear out. Floating caliper design more easily incorporates a cable-operated parking brake.