Rain Bird® A554800 WR2RFC-48 WR2 Series Rain Freeze Combo Sensor with 48-hour Hold. Rain and rain/freeze sensors are becoming “must have” components for irrigation systems these days. Rain Bird® designed the new WR2 wireless sensor to exceed the standard. With revolutionary features, this sensor saves time, improves system performance and enhances your reputation as a water management expert. Reliable signal transmission and other innovations deliver superior responsiveness to rainfall and cold temperatures, while user-friendly features cut installation and programming time in half. Choose your own rainfall set points and save up to 35% on water usage while promoting lush, beautiful landscape.