A mono is a hull that has one continuous wetted surface when operating at racing speed. A Mono must incorporate the following design characteristics and not exceed any of the dimensional restrictions.
- A hull that has no discontinuities between or steps in the wetted surface running at more than a 15-degree angle with keel, in plain view.
- No point on a hull cross-section shall be deeper in the water than the center keel (turn fins and trim tabs excepted)
- If trim tabs are used, they must be no more than 2 mm above or below the bottom surface at the intersection of the bottom surface, transom or ride plate.
- A lap straked hull is defined as a single wetted surface hull, with at least one strake on each side of keel.
Any number of strakes may be used;.
A strake is a strip of wood, metal, fiberglass or other material that is permanently attached to hull bottom or used in an overlapping “weatherboard” hull construction. (2) If Strakes are used between mid-point of hull length and transom, they must be parallel with keel. (3) Strakes may be of any cross-section, provided they are not deeper than 6mm vertically and 19mm wide horizontally. This measurement is made from the intersection (or projected intersection) of the hull bottom and strake when viewed from the rear.