The metal rolling is made of female dies in sandwich of "E glass" fibers and isophthalic resin with the centre in PVC for both hull and deck. The sandwich is interrupted only around the keel next to the bulb. The internal structure is hand rolled directly on the hull. The boat is ment to be a "regatta" boat for sailing schools or match races. However its interiors can include four berths, WC, wash-basin, small kitchen and motorization on board allowing a short cruise. A different version of the bad 27 is also available on request. The latter is made of advanced composites rolled up with epoxy resin with unidirectional tissues and biaxial E glass or with carbon steel and Kevlar, modified sail, carbon steel mast, customized appendix and deck equipment.