TELESIN 6 inch Dome Port Underwater Photography Shell and Dome Port Transparent Cover For GoPro HD Hero 4 3+ 3 OS467 Specifically designed for GoPro underwater photography to provide superior optical performance These are often referred to as half and half, 50/50, over under or split-level pictures. Easy to operate, nearly infinite depth of field, wide-angle lens and video and still image quality make the GoPro perfectly suited for this application. The Dome Port utilizes a custom made semi-hemispherical acrylic dome that has been optically matched to work with the GoPro lens, package includes GoPro housing and a floating handheld, all you need is a camera, turn it on and produce stunning imagery. The use of a semi-hemispherical dome eliminates the perpendicular angle between the backing plate and the dome. The benefits of this are the elimination of circular reflection and improved water sheeting while reducing the form factor and maintaining full front face surface area.