A fluid shock absorber of either the pneumatic or liquid type having a frustoconical threaded bleed plug for varying the shock absorbing capacity of the shock absorber. A shock absorber construction utilizing air or liquid having a piston which is expandable whereby expansion to the associated cylinder wall exerts a frictional resistance proportional to the variation in back pressure resulting from the variable restricted flow past the frustoconical bleed plug. A liquid-type shock absorber having a self-contained chamber and a frustoconical bleed plug arrangement wherein liquid from the cylinder is forced into the chamber through the frustoconical bleed plug arrangement. In certain embodiments the bleed arrangement is located in the cylinder wall, and in another embodiment it is located in the piston head.