Ken Winner – the "inventor" of wide boards - had a rule of thumb for the minimum distance from the trailing edge of the fin and the stern of the board to minimize the risk for "ventilating" the fin, namely 3" (approx. 7.5 cm).

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ken winner – the "inventor" of wide boards - had a rule of thumb for the minimum distance from the trailing edge of the fin and the stern of the board to minimize the risk for "ventilating" the fin, namely 3" (approx. 7.5 cm).