Hacking the Casio F-91W to Handle 1000 Psi
I don't know if I would even remotely trust that not to leak. The same watch is notorious for not having a quality seal and quickly fogs up in the shower. I would rather trade some meters and use straight up petroleum jelly injected into the casing at a high pressure; I'd be much more comfortable wearing that (and, yes, it is technically a liquid even at "freezing" temperatures).