A disc brake of the floating caliper type, comprising: - a supporting bracket which can be connected to a vehicle suspension, - a caliper body slidingly connected to the supporting bracket in a sliding direction and forming a first wall arranged on a first side of the caliper body and a second wall arranged on a second side of the caliper body opposite to the first side in the sliding direction, the first and second walls mutually delimiting a disc space for accommodating a portion of the braking band of a brake disc, - a first friction pad supported in the disc space on the first side of the caliper body, sliding relative to the caliper body, - a second friction pad supported in the disc space on the second side of the caliper body and fixed to the second wall of the caliper body, - a plurality of actuating pistons supported in the first wall of the caliper body which can be operated to push the first friction pad, in an actuating direction parallel to the sliding direction, towards the second side against the brake disc, causing the first friction pad to move towards the second friction pad and sliding of the brake caliper body relative to the supporting bracket until the brake disc is tightened on both sides between the first and second friction pad (12, 13), characterized in that: - the plurality of actuating pistons comprises a first piston connected to the first friction pad integral in translation in the actuation direction and a second piston associated with the first friction pad in a freely resting and detachable manner along the actuating direction, - the second piston forms a positioning surface which can abut, in the sliding direction towards the first side, against a corresponding resting surface (18, 18') which is either fixed or integral in translation in the direction of travel, either with the supporting bracket or with the first piston, the first piston and the second piston can be actuated selectively and independently of each other so that: - a rearward movement of the first piston towards the first side detaches the first pad from the brake disc, and - a rearward movement of the second piston towards the first side, with the positioning surface abutting against the resting surface (18, 18'), moves the caliper body together with the second pad towards the second side and detaches the second pad from the brake disc. - a supporting bracket which can be connected to a vehicle suspension, - a caliper body slidingly connected to the supporting bracket in a sliding direction and forming a first wall arranged on a first side of the caliper body and a second wall arranged on a second side of the caliper body opposite to the first side in the sliding direction, the first and second walls mutually delimiting a disc space for accommodating a portion of the braking band of a brake disc, - a first friction pad supported in the disc space on the first side of the caliper body, sliding relative to the caliper body, - a second friction pad supported in the disc space on the second side of the caliper body and fixed to the second wall of the caliper body, - a plurality of actuating pistons supported in the first wall of the caliper body which can be operated to push the first friction pad, in an actuating direction parallel to the sliding direction, towards the second side against the brake disc, causing the first friction pad to move towards the second friction pad and sliding of the brake caliper body relative to the supporting bracket until the brake disc is tightened on both sides between the first and second friction pad (12, 13), - the plurality of actuating pistons comprises a first piston connected to the first friction pad integral in translation in the actuation direction and a second piston associated with the first friction pad in a freely resting and detachable manner along the actuating direction, - the second piston forms a positioning surface which can abut, in the sliding direction towards the first side, against a corresponding resting surface (18, 18') which is either fixed or integral in translation in the direction of travel, either with the supporting bracket or with the first piston, - a rearward movement of the first piston towards the first side detaches the first pad from the brake disc, and - a rearward movement of the second piston towards the first side, with the positioning surface abutting against the resting surface (18, 18'), moves the caliper body together with the second pad towards the second side and detaches the second pad from the brake disc.