Abstract: A locking structure for an article includes a bladder including a first barrier element attached to a second barrier element to define a chamber having an interior void. A locking system includes locking elements that each attach to at least one elastic element. The locking elements each include at least one interface surface. The interior void of the bladder operable between a first pressure to move the locking system to a locked state and a second pressure to move the locking system to an unlocked state.

Abstract: A shock absorber for use to interconnect the polish rod of an oil well with the pumping unit in which the pumping unit includes a hanger bar having an opening therein receiving the polish rod, the shock absorber employing a tubular body axially receiving the polish rod, the body being supported on the hanger bar, and the body including a plurality of discs of elastomeric material, each having openings therein, and including a top plate secured to the polish rod with a polish rod clamp so that on up stroke of the pumping unit the elastomeric members are pressed and the openings therein form an air cushion to assist in alleviating shock transition from the polish rod to the pumping unit.