GE Security Interlogix Simon 3 Simon XT Wireless Freeze Sensor

Easy to install, I will only know if it's working properly if the temperature in the house drops to below 40° which I hope it never does.

Do not buy this. It does not work. I bought it to complement my Frontpoint security system. I wanted monitor the temperature for potential freezing situations. I installed as directed by the Frontpoint tech. There were NO instructions in the package. It worked well for about an hour. Fortunately I armed the system and went to dinner to test. I got 4 alarms for low temperature. I know the house was at 65°. That's 20° above the alarm point. Ultimately I had to disable. Now I have a $50+ piece of junk plastic stuck to my wall. I'd give this zero stars if I could.