For lenses with a 110 to 170 degrees angle of coverage ikelite acrylic domes are injection molded specifically for underwater photography and represent the finest optics in the industry domes are recommended for lenses 28mm and wider to preserve the full angle of coverage zoom lenses that do not focus to 12 inches 30 cm require a 4 diopter close up lens accommodates lenses up to 25 inch 63 cm long and 33 inch 84 cm in diameter measure your lens or use see ikelites port finder o