Sealing "waterproof" electronics

[4runner]

Other than a waterproof drybag, does anyone know of any waterproofing products that can be applied to a handheld "waterproof" VHF, camera or GPS to keep the water from getting past the battery doors. It seems like a fairly common problem with many manufactures and products. I've tried 303 on the rubber gasketing on a Garmin GPS12xl (old unit no longer supported) with no luck.

Thanks

[David M]

There are lots of waterproof cases that come close to the shape of the device. Is that what you are looking for?

Waterproof VHF Radio Case, No Signal Loss - Floats

Waterproof Camera Cases, SLR, Digital SLR, Underwater Housings

Waterproof GPS Cases

I found these by doing a Google search. There are lots more to choose from.