Not that I noticed.
Ok now this might get a bit technical for some but try and keep up
The black wire conects to a 10ohm resistor which goes through a small hole in the black plastic bit. On the top you can see a small screw (next to the white wires). The resistor wire wrapes arround that screw where it joins the end of the reed switch. The switch is located inside the black bit and is attached at the other end to the yellow and green wire by a simillar screw on the back of the black bit.
NOTE: People who are noty as clever as me and can not follow the above detailed explination should refer to the Collins book of advanced electrical terminolagy
ATB
Mark Chase