So I am working with solenoid valves, and I hear it opening when I put a battery up to it, I hear the valve opening, but I don't actually SEE it opening. Here's a link to the valve I'm using. It's not very common.
https://www.google.com/search?q=solenoid+valve&biw=1719&bih=897&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjy55WX6PLOAhXm5oMKHVwDD2IQ_AUIBygC#tbm=isch&q=12v+solenoid+valve&imgrc=RTYeFVurDn0P9M%3A