Robust foot pocket, square profile and reinforced edges. All this is surprising if we consider an ultra-light fin like the Seac F1 S which, in just 730 gr., summarizes all the quality and the search for underwater performance typical of the Seac brand.The Seac F1 S features a blade designed to minimize the effort and release an unprecedented thrust in such a light fin. The Ultra Flex technopolymer joins the rigid sections of the blade to guarantee flexibility, ease of return of the fin and therefore less effort. This special structure also has a high degree of impact resistance, even at low temperatures, and the protections on the side-ribs ensure greater durability.The addition of the "S" differentiates them from the previous Seac F1 sisters and indicates the new Sling Strap system with heel support that facilitates the fit and improves comfort. The soft, but resistant elastic band, makes the ankle work easier and the heel piece (robust, wide and color matching the blade holds firmly fin and relieves pressure on tendons.The foot-pocket has been designed with a combination of technopolymer and thermoplastic elastomer to stabilize the fit and has a practical non-slip sole with raised rubber profiles.Although designed for recreational use, Seac F1 S fins therefore have many qualities usually reserved for professional fins only. The attention to higher level performances, also for products dedicated to the general public, has always been one of the strengths of the Ligurian parent company Seac which, since its birth in 1971, has invested heavily in research and development to spread the innovation in the diving market.