This Hozelock pressure regulator reduces your tap water pressure for automatic watering systems Includes connectors for both 13mm and 4mm hose and an accessory adaptor allowing you to fit the pressure regulator onto a hose connector It is recommended that a Pressure Regulator should be used in Automatic Watering installations as it optimises the water pressure of the system It will fit both ½ and 14 BSP taps Will connect direct to a tap water controller or even to the end of a hose Compatibility 13mm4mm