Abstract: A piston ring grinding apparatus providing piston rings of consistent gap is disclosed. The piston ring grinding apparatus has a base member with a piston ring grinding means mounted thereon. The piston ring holder is rotatably mounted on the base member for movement of a piston ring mounted thereon into and out of contact with the grinding means. A gauge means are in operative association with the piston ring holder and are mounted on the base member in a position to gauge rotational movement of the piston ring holder.

Abstract: A portable bullet-proof shield for use by law enforcement agents, is horizontally curved and of sufficient height and width to protect substantially the body of the user when the shield is being carried or is resting in a free-standing mode. The shield includes a viewing lens assembly near its top, an adjustable shoulder suspension strap, a horizontal hand grip bar, and elastic horizontal stand-off straps on its interior side to protect the body against "blunt trauma". The shield has a frontal skin formed of aluminum or high-impact plastics behind which is disposed a penetration-resistant wall consisting of multiple layers of woven synthetic fabric which may be laminated or non-laminated. A single layer of waterproof synthetic fabric or rear skin formed of high-impact plastics defines the interior face of the shield. The shield possesses a frame consisting of top, intermediate and bottom horizontal bows which are riveted to the shield primarily at opposite side rearwardly projecting portions of the shield.