I think the nox uses a wm08 module at a different frequency to the wm10, you can get adapters to fit standard plus to the micro one on the nox too.
Actually now I think on it aint the noxs...
Yep just be polite and ask face to face, "sorry to bother you but was wondering if you allowed people to metal detect on your land"
BUT take no as a no not a please keep talking, thank them and walk...