Its an anti theft kind of alarm - contacts in all the compartments with a remote to arm and disarm - works when a compartment is opened and has a mode to detect vibration - I don't really ever use the vibration part but always figured when the bad guys are looking for a boat at some motel etc to hit they won't pick the one with the little alarm armed light flashing - if they did it is a very very loud alarm.
I actually had a system issue I had a question about and been contacted on it - don't get me wrong the one he put in has worked perfectly and it was put in in early 2013 -