I have a Radio Shack Keyless Electronic Vehicle Alarm (Model 49-751) with no instructions. It is apparently an old one with no remote control (there is no antenna sticking out of it). There are eight connectors on the front of it, but nothing shows what they are for. They are only numbered 1 through 8. On top of the module it says Mobile Alert. It's about 3 inches by 5 inches and about 1 1/2 inches thick.