pic: How do we operate this valve?
 

Re: pic: How do we operate this valve?
 

Happy to try to help, but first:
It looks like this is a 1/4 NPT valve.

Re: pic: How do we operate this valve?
 

I'm pretty sure that's 1/8" NPT. That chromed fitting looks like the standard 1/4" OD tubing to 1/8" NPT fitting. Based on the fingers in the picture, that tubing looks to be a plausible 1/4" OD, and nominal OD for 1/8" NPT is about 0.4". So, while it's a beefy valve, that still appears to be in compliance with the rules. A good measurement to double check would be in order.

Re: pic: How do we operate this valve?
 

The two parallel terminals are most likely the ones you want to connect to. Grab your ohm meter and check the continuity between each of the terminals and the body of the valve. One should show infinite resistance between it and the other two and may show near zero resistance to the body of the valve. The other two should show measurable resistance. Or you could just google the part number and find the data sheet for that family of valves.

Re: pic: How do we operate this valve?
 

Not trying to be a wiseguy, but the manufacturer's specification sheet can be your friend here...

Re: pic: How do we operate this valve?
 

You're probably right. Sorry OP!