The Brass Nozzle Plug is used in place of a mist nozzle on all outdoor mist cooling systems. These plugs are used to replace nozzles in the off season when the mist system is not used and the mist nozzles are being stored. Nozzle plugs prevent debris and insects from entering the mist line and clogging the system. They are also useful to plug off openings when less mist is desired