anyone know what thread they are ?
i thought bsp, but its coarser
cant find my thread gauges
alternativley, if anyone has an old regulator i can use for the thread, i may loose interest in trying to find out what it is
the reg dont need to work btw

I have 3 regs. 1 in use but 2 spare. I'm not sure whether they would be of use to you but if one of the spare ones fits then you are welcome to make use of it. The smaller one (no gauge ) has a nut on it to fit a female thread. The larger one (with gauge & to fit bigger bottles I think ) has a nut with male thread to fit a female bottle.

Clive.

Possibly 1/8th"NPTx27tpi