This Naiad fin is pressed onto its splined shaft, and stays put without fastenings. Removing it requires special equipment, though. Note the narrow winglet at the tip of the fin to make it more efficient.
Absolute Yachts employs magnetic glasses on the 73 Navetta. The glasses are stowed upside down in a dedicated magnet-ready locker, and all table tops have a ferrous layer that allows the magnets to grip. This innovation can help keep glasses upright in a seaway, and keep spills to a minimum.
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