The Reliable Rain Sensor With Instant Shut-Off The reason to install a rain sensor is so an automatic irrigation system that is scheduled to run will be able to shut off and NOT run when it is raining, right? However, most rain-sensing devices must first accumulate a set amount of rainfall before a switch is activated that interrupts the circuit from the controller and shuts off the system. In that “accumulation time,” the system will continue to water, giving the appearance a precious resource is being wasted…exactly the opposite impression a municipality, a business or an upstanding citizen would like to convey. Only the Hunter Rain-Clik™, with its unique Quick Response™ feature, can command a controller to shut off immediately – not after a quarter- or a half-inch, but right when it starts to rain. And, unlike any of its competitors, the Rain-Clik™ can be mounted in a variety of ways: on a rain gutter, on conduit, with a telescoping extension to bring the unit away from an eave, or in the standard method on a flat vertical surface like a wall or fence.