What is the gap allowed between 5811 sensor and magnet?

The maximum recommended gap between the wireless transmitter and magnet on a Honeywell 5811 wireless thin door and window contact is 0.75” or 19mm. If the gap is wider, the 5811 may be in fault even when the door or window is closed. When mounting the Honeywell 5811 contact, the transmitter should be on the door frame or window frame, and the magnet should be mounted to the door or window.