The Ventec MDR Magnetic Door Retainer is a surface mounted electromagnetic door holder/retainer designed to operate only with self-closing doors. The unit sits on the wall behind a fire door and magnetically holds the steel keeper plate which is fitted to the fire door. If a fire is detected, or the power supply is interrupted, the fire door retainer releases the door and allows it to close under control of its mechanical door closer.

A release button is fitted as standard to enable a door to be manually released if required.