11 Structural plumbing parts, namely, fittings in the nature of ball valves, water hammer arresters, and rapid adjust trip flush levers; structural sink and bath parts, namely, overflow plates, sink strainers; structural toilet parts, namely, dual flush toilet valves, toilet flappers, toilet fill valves; toilet fixtures and fittings for sealing the closet flange position between a toilet and the floor; namely, non-metal sealing rings specially adapted for toilets; water filtration units and water softener units comprised of water purification tanks, sediment pre-filters, and copper-zinc, mineral stone and activated carbon filters; plumbing fittings, namely, floor drains, roof drains, area drains, deck drains, clean out drains and shower drains made of metal or plastic for use in industrial, commercial and residential buildings; non-metal plumbing fittings, namely, air valves for drain pipes, waste pipes and vent pipes; tub parts, namely, non-metal tub overflows for pipe leakage