Just one note I used telephone wire for the x50 and learned two things.
1. green and red wires are swaped on some telephone wires.
2. the detector will not work if you reverse power it.
If you use telephone wire instead of the provided power cord it saves alot of room and hassel just remember to look at the wire color and compare. If you are looking at the detectores wires:
Green = ground
Red= power
Yellow= mute
Black= LED (requies resitor)