A disk brake assemblage providing an improved arrangement whereby the brake pads and supports therefore may be changed with a minimum amount of disassembly of the disk brake assemblage. The brake assemblage is provided with an annular cylinder and an annular piston operable therein and comprising a brake cylinder device operably disposed between a pair of backing plates and brake pads which are adapted to frictionally engage respective brake disks or rotors. Both the cylinder and the piston are provided with axially projecting lugs or members normally engaging correspondingly formed recesses on the brake pad backing plates for retaining the brake pads and plates in the operable position. By axially squeezing or displacing the cylinder and piston toward each other, the lugs are displaced out of the recesses to permit the brake pads and backing plates to be removed and replaced.