The Neo-Pure Solenoid Connection Module MOD-SOL1-NP used in connection with all Neo-Pure UV disinfection systems. This Module requires a NORMALLY CLOSED line voltage solenoid valve, which is not supplied and must be purchased separately. To install, simply connect the power supplied lead from your solenoid valve to the controller. The MOD-SOL1-NP features a manual override mode for when an emergency occurs or you have for untreated water.