Rain Sensor: This is the standard cost-effective rain sensor that can be connected to any irrigation controller that has sensor ports. It will turn the irrigation system off in the event of enough rain. You can adjust it so it requires a reasonable amount of rain (not just a brief drizzle) before it will turn the irrigation system off. Mount it on a fence or post away from overhanging obstacles. Requires a twin electrical cable to be taken back to the irrigation controller.