Glossary · Rules & safety
Box rule
Also called: Jauge à restrictions, open, classe open, jauge ouverte
A rule that sets limits (dimensions, materials) and leaves designers free within them.
A box rule defines a “box”: as long as a boat stays within the limits, anything goes. It encourages innovation, and so very different boats, at the price of high budgets. IMOCA, Class40 and Ultim are box-rule classes, sometimes with standardised parts.
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