Good to see sail makers trying new things, from ABC windsurfing
http://www.abcwindsurf.eu/index.php/materiali/vele/3199-abc-focus-welcome-to-the-future-le-vele-asimmetriche-di-heru-sails-a-challenger-sailsABC: What is so different from traditional sails?
HS: Externally and aesthetically few things, the differences are inside, in fact wea double surface which creates a "strange" thickness on the sail that looks like a pocket of very large tree, in practice you do not see the classic depth but almost convex surface.
We were able to achieve, for windsurfing, a wing sail similar to other modern wing surfaces designed for boats and catamarans.
Obviously our wing sail is a weapon as a traditional sail, mast and boom as standard

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