The SF506ES Wireless Smoke Detector is for use with the Tek-CARE 500 Wireless Emergency Call System and is intended for indoor, open area protection. The SF506ES is self-monitoring, alerting the user when sensor maintenance is needed or batteries are low and automatically supervising the radio link. Additionally, local test capability allows the user total visibility of the detector's functionality with a test button. The SF506ES provides two LEDs (green and red) that will indicate power up, sensitivity out of range, low battery, smoke alarm and normal (standby). See IL881 TekCARE500 Installation Manual for LED indication details.