The 120T/4473 requires that a 3/4" hole be drilled for the switch and 3/8" hole for the magnet. The 3/4" switch mounting is desirable since the extra wire and connections can bemore easily inserted into the larger hole for concealment. Also, should the need arise fortesting or replacement, it would be easy to pull the switch, extend the extra wire andaccess the original connections. Installation is further enhanced by using a smaller 3/8" diameter magnet to avoid the need to center a larger hole in a 1" to 1 1/2" thick door or window. This will allow you to offsetthe magnet should it be required.

The 120T/4473 switch set was developed for and should only be used in openings withwooden or aluminum frames.