The 40$ 30m Waterproof Slave Strobe

A very easy one for underwater photographers on a budget.
For years I had a Godox CF-18 flash taking dust on a shelf.
Those flashes are dirt-cheap and I couldn't care to risk one for diving but I could not find any housing for it until I found a 30m waterproof utility case with the exact same dimensions!

The flash: https://www.ebay.com/itm/CF-18-Digital-Slave-Flash...

The case: https://www.ebay.com/itm/Waterproof-Box-Case-Holde...

The tripod screw: https://www.ebay.com/itm/NEW-Pro-Type-1-4-20-Tripo...

The glue: https://www.ebay.com/itm/85-oz-LOCTITE-Epoxy-QUICK...

- Glue the tripod screw on the back of the case.

- If you are using optical fiber for triggering the flash, you can also use a section of a large pen, that's roughly the same diameter as an Intova optical plug.