Abstract: An improved brake actuator and method of assembling a cup-shaped housing on a housing member of a brake actuator, wherein the housing member has an open end, an annular radially projecting rib adjacent to and surrounding the open end and a plurality of spaced channel-shaped transverse depressions in the radial rib extending toward the open end of the flange case, a cup-shaped metal cover including a tubular open end having an inside diameter initially less than the outside diameter of the annular radial rib of the housing member, wherein the tubular end portion of the cover is pressed telescopically over the radial rib of the housing member, thereby simultaneously deforming the tubular end portion of the cover into the channel-shaped depressions in the rib of the housing member and stretched over the radial rib, thereby preventing rotation of the cover relative to the housing member.