A piston assembly including an integral piston chamber with an increased volume that is maximized by providing a mounting arrangement whereby the piston can be mounted to a structural member such that the piston chamber surrounds at least two sides of the structural member. A gas damping passage is disposed in fluid communication with the piston chamber and is dimensioned such that pressurized gas transferred through the gas damping passage can dissipate kinetic energy acting on the piston assembly. The piston chamber can therefore utilize space adjacent the structural member to which it is mounted thereby resulting in a piston chamber of a greater volume than prior art designs. A gas spring and gas damper assembly utilizing such a piston assembly is also included.