 Mast-aft rigs are uncommon, but are found on a few custom, and production sailboats.Many mast-aft rigs utilize a small mainsail and multiple staysails that can resemble some cutter rigs.A cutter is a single masted vessel, differentiated from a sloop either by the number of staysails, with a sloop having one and a cutter more than one, or by the position of the mast, with a cutter's mast being located between 50% and 70% of the way from the aft to the front of the sailplan, and a sloop's mast being located forward of the 70% mark.