Skylink FS-433W Wireless Flood Water Leak Alert Alarm Safety Protection Security Sensor | Affordable, Easy to install DIY Accessory for SC Series Systems NO MONTHLY FEES and easy DIY (Do It Yourself) installation UP TO 100 FOOT OPERATING RANGE in open area. WIRELESS - BATTERY POWERED with low battery indication: be informed when the sensor`s battery is low before it stops sending signals Compatible with Skylink security systems, SC-10W, SC-100W, and SC-1000W LIFETIME SUPPORT - Toll free 1-800-304-1187, support@skylinkhome.com "