In reply to:
Ah the black sausage joints. The're actually supposed to be mounted at the overhead cable fixing so typically the '3M' won't be viable from the ground (unless you live in a bungalow). If thats what the OP is discribing then all is well (probably).
Yep, without going out of my front door (too cold) I can say that there is a box mounted on the roof right next to the cable tensioner where the span goes over to the pole.
The span used to hang too low and would occasionally get ripped off by car transporters, so had it replaced quite a few times.
A couple of years ago though a new telegraph pole was installed at a higher level and it's not a problem now.