A caliper of a disk brake suitable for co-operating with at least one pad, wherein the caliper comprises a caliper body, provided with a housing for accommodating the pad, and thrust means suitable for acting on the pad in order to cause it to abut a braking surface of a disk of the disk brake having an axis of rotation (X-X), in order to perform a braking operation, the pad comprising - a support plate having a rear surface, on which the thrust means act during a braking operation, a front surface facing the braking surface of the disk, a lower surface and an upper surface, opposite the lower surface wherein said upper surface does not bear on the caliper body; - friction material (26, 28), supported on the front surface of the plate, which defines a swept surface on the rotating disk; - a protuberance, of the upper surface which extends from the plate, being positioned outside the surface swept by the friction material; - a support portion of the lower surface of the plate which is positioned outside the surface swept by the friction material; - reaction means suitable for transferring the braking force generated during a braking operation to the vehicle chassis, wherein the reaction means comprise a reaction region which extends at the location of a circumferential end of the plate; wherein the caliper comprises: i) a suspension pin for the suspension of the pad coupleable in a seat housed in the protuberance; ii) a support protuberance co-operating with the support portion positioned outside the surface swept by the friction material; iii) a rib, suitable for co-operating with the reaction region of said pad; characterised by the fact that the rib and the reaction region are parallel with a median radial axis (M-M). - a support plate having a rear surface, on which the thrust means act during a braking operation, a front surface facing the braking surface of the disk, a lower surface and an upper surface, opposite the lower surface wherein said upper surface does not bear on the caliper body; - friction material (26, 28), supported on the front surface of the plate, which defines a swept surface on the rotating disk; - a protuberance, of the upper surface which extends from the plate, being positioned outside the surface swept by the friction material; - a support portion of the lower surface of the plate which is positioned outside the surface swept by the friction material; - reaction means suitable for transferring the braking force generated during a braking operation to the vehicle chassis, wherein the reaction means comprise a reaction region which extends at the location of a circumferential end of the plate; wherein the caliper comprises: i) a suspension pin for the suspension of the pad coupleable in a seat housed in the protuberance; ii) a support protuberance co-operating with the support portion positioned outside the surface swept by the friction material; iii) a rib, suitable for co-operating with the reaction region of said pad; i) a suspension pin for the suspension of the pad coupleable in a seat housed in the protuberance; ii) a support protuberance co-operating with the support portion positioned outside the surface swept by the friction material; iii) a rib, suitable for co-operating with the reaction region of said pad;