If you are referring to the REM units, they essentially were fixed to lifts to monitor( via phone lines) vital inputs ie (safties), then send that signal to the office. The idea being to be able to send mechanics to broken down lifts ahead of a call out being lodged by the customer to help reduce call back numbers. In my experience they never worked all that well, and don't effect the running of the lift whether they are in service or not. In fact I think the service isn't really working any more in our country.