No worries. I canceled my order and now looking for FG1625.RAL said:I'm afraid I may have sent you astray when I said all the glass break detectors I've seen are 4-wire. Honeywell makes a line of addressable detectors that all connect together on a 2-wire loop. They call this system V-Plex. These are usually used in commercial/industrial environments where a lot of detectors are needed and creating a simple loop saves a lot of wiring effort.
Unfortunately, you won't be able to use them with the M1. You'd want the plain FG1625 instead.