Pentex Mylar is ideal for small jibs monotypes (J80, Melges 24.), it allows a good report/ratio held/weight for light genoa sails and medium to 35 feet. Rovings high Kevlar module or Carbon: these rovings give to the sails astonishing stabilities of form. In the surventes, the blocking of rovings avoids all the deformations and the totality of energy is transformed into bearing pressure. The boat accelerates and gains in course.