11 Backflow preventers in the nature of plumbing valves; plumbing fittings, namely, bath drains; plumbing fittings, namely, structural drain parts, namely, sink strainers, traps, bends, tubing, tail pieces and waste arms being bath waste kits; plumbing fittings, namely, faucets, faucet sprays, faucet handles, water spouts, faucet filters; plumbing fittings, namely sill cock; plumbing fittings, namely, hose bibbs; dampers namely control devices used in air ducts to regulate the flow of air; air diffusers being parts for air conditioning units; dampers, namely, control devices used in air ducts to regulate the flow of air; drain pans specifically adapted for water heaters to protect from condensation, leaks and overflow; equipment for use in hot water heating systems, namely, expansion tanks; valves as parts for radiators; plumbing fixtures, namely, faucets and replacement parts thereof; pressure relief valves for plumbing use and replacement parts thereof; flush levers for toilets.