In Oct. 2022, after a catalytic converter was stolen off 1 of my vehicles, I google alarm system, and I choose Fast Guard. I bought 2 units. When they arrived, I installed them on my vehicles. Within a month, they batteries needed to be replaced, which I did. In Dec. 2022, 1 off the units needed batteries replacement again. After several calls, finally was able to talk to someone, and he stated that it appeared that the unit was probably one that had been sitting in the warehouse for a long time. He said he would send me another unit, which he did. Once I got the unit, I changed the batteries. After about 2 months, the unit stopped working. The beeping sound was so low you could hardly hear it. Replaced the batteries again, but that did not work. I started calling the company at different hours, was unable to talk to anyone so I left my name and phone number. NEVER heard from anyone. Sent several emails to company, still no response. So I shipped the unit to the company, which shows they received it, wrote a letter detailing the problem, still haven't heard from them. So my advise to anyone looking for an alarm system, do your homework. If you want to buy from them, and have trouble with the system, don't expect them to call or email you back!!!!