Well, at this stage, I don't have any.
I am pricing them and getting the specs.
The ones I am wanting are normally closed, and with 12v DC they open.
So the power opens the valve.
Removing the power - I thought - closes them.
Alas not all. And the person with whom I was talking say those kind cost.
In the mean time I have "discovered" washingmachine solenoids. They seem to be what I want, though they don't exactly have an ouput thread. It is more a spigot. But that would suffice. I just use smaller pipe.
I have sent off a request to a supplier, but what I am asking is not the usual questions so I am not holding my breath for a reply.
Ah, the quest continues.