Motorised valves - open when power off

[Keefiedee]

I need some 28 mm motorised valves that are open when there is no power rather than closed as is more usual.

I don't suppose I can get them from eBay, but need to do a Google search. Trouble is, I'm not sure what they're proper name is to search on. Can anyone help, or give me any links to sites where I could get them?

TIA

Keith

[Dave Osborne]

Here's a starter for 10:

[BraileTrail]