The forward 15 mm of the hull shall be made of elastomeric material. From the foremost point of the hull to the point where the bow profile is 45 degrees to the waterline, the thickness of elastomeric material shall not be less than 5 mm. The boat shall carry, either painted, engraved or molded in, the boat's national letters and registration number. On the external surface of the hull or deck these marks shall be displayed clearly and legibly, with a minimum height of 20 mm. The waterline shall be established with the boat floating in fresh water in sailing trim and dry with the heaviest rig, including spinnaker and spinnaker boom in their normal positions if used.
Waterline denotes the water surface level remote from the hull.
The measured waterline length is the horizontal distance at the waterline between the inboard edges of the two waterline measurement marks placed as in 3.5.3 and 3.5.4. The boat's waterline endings shall not fall more than 30 mm inboard of the inboard edges of the waterline measurement marks. 3.5 Measurement Marks 3.5.1 Measurement marks shall be of a color which contrasts strongly with the color of the hull and shall be of uniform width between 2 mm and 6 mm wide. A waterline measurement mark of minimum length 25 mm shall be placed near each waterline ending. The aft edge of the forward waterline measurement mark shall be placed forward of the forward waterline ending.