This Ikelite 8" Dome Port is for wide angle lenses when used in Ikelite digital SLR housings. A port body (not included) is required to attach the port to the housing. The 8" dome port reduces edge distortion on photos taken with certain fisheye and super wide-angle lenses. With this port kit over / under photos are now possible. The port cover that goes over the dome with the shade attached is included.