This is a simple low cost waterproof DIY housing for my 2 GH13's. It's not for underwater only ON water, will take splashes etc. I use this shooting from a Jetski/boat on the ocean etc.
It allows use of the 14 - 140 kit lens with ND to protect lens glass, the waterproof sleeve expands to full zoom and protects quite well. The controls are electrical cable glands and controls Focus/Exposure lock (one push sets focus and locks it, the others are record, power and LCD/EVF switch. These controls are all i need, camera runs shutter priority 1/100 and auto ISO. Allows more protection than say a Kata soft camera cover.
In the process of putting smaller button controls like the LCD/EVF one.
Simple steady cam base (all plastic) that goes with it. No gimbal, you just hold it at the balance point under the top handle (hand rests on the foam donut) A gimbal moves too much on a jetski/boat. The point of all this gear having next to no metal parts, is it all can be taken as carry-on luggage when i air travel to OS events.