100m Submersible Green Laser Pointer 150mW for Scuba Diving

I took it diving once, and it ran for almost an hour nonstop until the battery ran out, without any water getting in. The beam is clearly visible and much brighter than some so-called "10,000mW" lasers I bought in other shops before.

I have tried using this laser to point at marine life in the deep sea, and it works great! I will be buying two more soon.