On 10/01/2020 13:12, Andy Burns wrote:
Andrew wrote:

There should be a special plastic fitting that reaches down to the
'stop cock' which is turned 90 degrees from full on to full off.

Mine has a 6-sided end, like an allen key, and about 10 mm
further up the shaft are two rectangular 'shoulders'

A "normal" stopcock key fits a plastic stopcock here

https://screwfix.com/p/stopcock-key/71652

£28 !!.

It looks like it is designed for metal stop cocks, ones that
need some welly to turn on those blue-moon occasions when you
need to.

A external combined water-meter/stop cock box wouldn't need
anything that strong, because the stop cock is plastic and only
turns 90 degrees, but the extra reach could be necessary.

The key supplied by Southern water is as described above.
I have just measured it and the 'hex' end measures 10mm
across two opposing flats, so assuming the stop cock
has a hex socket, I would just get a hex fitting for
a 3/8 socket set, with a long extension bar and Tee handle.

This one would be a cheaper alternative :-

https://www.screwfix.com/p/rothenber...le-520mm/9638k

- assuming that the 'flat' section engages with the slots in
the plastic stop cock.