Ikelite 5506 Underwater Housing Port for SLR Cameras - Flat Port for Professional Underwater Photography - Perfect for Scuba Diving, Marine Exploration and Aquatic Sports

Flat ports are recommended for standard, macro and telephoto lenses. Due to refraction, flat ports reduce the angle of coverage of a lens and magnify the image. This makes the flat port ideal when using standard, macro or zoom lenses to shoot small subjects.