Abstract: The damper includes a housing assembly and a piston assembly with reciprocates within the cylindrical walls of the housing assembly. The piston assembly is formed from two disks which are spaced apart by a spacer with includes radially and longitudinally oriented planar projections which extend to a position radially inward of a periphery of the disks. The distal ends of the projections form longitudinally oriented surfaces upon which a toroidal seal slidably rides. At least one of the longitudinally oriented surfaces includes an air communication groove in communication with a groove on the trailing disk which extends to the periphery of the trailing disk. When the piston assembly is retracted from the housing assembly, the seal engages the leading disk thereby inhibiting air from flowing through the air communication groove thereby effectuating damping.