I bought a battery powered wireless home alarm that is armed and disarmed with a remote. Seems to work although no one has tried breaking into my boat to test it. I just reach in and set it on the floor and arm it right before closing up boat cover. It triggers after a 30 second delay when the boat cover is moved. The delay gives you enough time to disarm it before it sounds when you want to turn it off. Only drawback is it will trigger if it is windy enough at night to cause the boat cover to move. Got it online at home depot, only cost about 20 bucks.