Snorkeling and diving had better choose transparent silicone skirt edge, such light will be a few brighter, reduce depressive feeling.  The lens design depends on personal interests. Some people like the single lens design without shielding, while others like the double lens design with small volume and large viewing Angle.  

Cold water diving  

Many cold water professional divers use full-cover goggles to keep warm.  If you are using a regular mirror, a large hood is recommended to cover the skirt and forehead of the mirror.  American divers in the Antarctic use a conventional diving mirror with a balaclava-style diving headgear, leaving only a bite opening to maximize cold water isolation.  

Underwater photography  

For photography and video, these divers like to use a small volume pair of mirrors with a black silicone skirt.  This avoids the effects of distracting light and gives a clearer view of the target and viewfinder.