N100 Extension Ring 40The N100 Extension Ring 40 is part of the N100 Port System and can be used to add 40mm effective length to an N100 Port setup. See Port Chart for more details on choosing the correct extension and port. Technical Specifications Depth Rating 150m Port System N100 Weight Port Opening Diameter Port Diameter Body Material Anodized Aluminum Alloy Port Material Port Coating Port Shade Material Removable Port Shade Spare O ring 90141 split Support &