In underwater photography, there are a lot equipment such as Waterproof case, Strobe lamp, Filter, and Dome port.
Dome port is an additional equipment for camera water case. There are two kind dome for action cam water case. Universal type with no waterproof case included, and the special one (with waterproof case). Here in Aceh, i sell special dome for Yi Action cam 4k and Dome for Gopro hero 5
Link Yi cam 4k dome : https://www.bukalapak.com/p/kamera/action-camera/aksesoris-action-camera/7fmhlk-jual-6inch-dome-yi-4k?from=&product_owner=normal_seller
Link Go Pro Hero 5 Dome : https://www.bukalapak.com/p/kamera/aksesoris-kamera/aksesoris-lainnya-896/7fmg5n-jual-6inch-dome-gopro-hero-5?from=&product_owner=normal_seller
here some pict that i captured using dome