Luckily it has it's own battery, solar charged, and the horn is mounted on a 20 foot pole. When I first got it went to test it with a 20 amp battery charger, it just buzzed and zapped the charger's amp meter. I thought I got ripped off. It wasn't till I connected it to a battery that it worked, sort of wished it didn't since I was only two feet away. Works great for an alarm, you can hear it from two miles ...