I guess the subject says it all...

It seems like it's made of aluminum or an aluminum alloy, because of how light it is, but I'm not sure, and I know we have a bunch of engineers here. I'm talking about the valve itself, not the pin (which seems like it may be stainless steel).

I need this to find the coefficient of thermal expansion so I can make an insert with a friction fit (insert goes into freezer, valve into oven type of deal). I want to see if I can make a decent one (a winter project challenge). If it doesn't work out, I'll just get the one available (*cough* pineapple racing).

 

Well, it's definitely aluminum, I just can't tell you what KIND of aluminum :P