I had to laugh, sorry. As cool and funny as this may be, and I'm sure you could get it to work; I think a threaded cap that would stay in place better seems more appropriate. I've lost a few Martinis over the years letting the lid fly off. Maybe a Stainless Steel Thermos? For zero pressure you could drill a small 1/16" hole in the plastic cap. I'm probably going to use Tunagloves idea. An inexpensive power steering reservoir from a BMW I think it was. Purchased on E-Bay. It's on here, if you search. Good luck.