Ikelite DL 8 inch Dome Port with Extended BaseIkelite DL 8 inch Dome Port with Extended Base IK75342 Ikelite Product Number 75342 Product Details An 8 diameter dome made of optical grade acrylic. Comparable quality to glass yet significantly lighter and easier to handle, especially at the surface of the water. Not compatible with external filters. This port features a longer base which is required with certain very large diameter zoom lenses. Refer to the DL System Port Chart for compatibility.