13 PLUMBING SUPPLIES-NAMELY, DEVICE FOR CONTROL OF WATER HAMMER OR KNOCK IN PIPE LINES; FIXTURE SUPPORTS FOR WALL HUNG TOILETS, LAVORATORIES, URINALS, SINKS, DRINKING FOUNTAINS, ETC.; DRAINS FOR ROOFS, SHOWERS, FLOORS, SCUPPERS, SWIMMING POOLS, ETC.; AND INTERCEPTORS FOR OIL GREASE, PLASTER, SEDIMENT, ETC.