Review on BESTSUN Flashlight Waterproof Underwater Professional by Michael Gilmartin

These flashlights are not suitable for diving. The switch design is not waterproof, and when wet, the magnet inside will rust and cause failure. I bought two and after our first dive and fresh water cleaning one failed. Was replaced under warranty but I was curious as to why it failed so quickly. The weak link is the switch or the magnet in the switch. My solution was to buy some 2mm x 3mm magnets and lightly coat them with dielectric grease when assembling. However, I didn't have to do this with a real dive light.