Get Closer Minimum Focus Distance and wide angle.
The UCL-G165 SD lens is a so-called "wide close-up lens" specifically designed for GoPro cameras. It supports closer minimum focus distance underwater. The depth of field (DoF) underwater will be 5cm to 35cm for GoPro.
The maximum angle of view of GoPro HERO is approx. 150 on land which will narrow down to approx. 94 when the camera is diving.The UCL-G165 take the angle back - and more.
A Must-Have part of your GoPro Kit.