How do I make this gadget waterproof?
I'm developing an electronic application which looks more or less like the picture. Diameter abt 40 mm. I need to find a way to make this waterproof, at least down to 5 meters. Another requirement is that the 2 knobs need to have a tight wrap around them (they are tactile switches), which means that I can't just put it in a waterproof plastic bag.
I have looked into shrink wrapping, which would make the 2 knobs stick out like I want, but I have understood that the seals in a shrink wrapped product are usually not too watertight.
I would also like a wrapping that gives a smooth upper surface, if this is possible.
Maybe shrink wrap and watertight tape over the bottom seal would work? Can you think of other ways to do it?
Thanks in advance!