The Castelli Men's Sleeveless Free Sanremo Suit boasts water-shedding, wind-cheating, highly ventilated functionality, and we think the advantages over a jersey/shorts pairing are obvious. In a non-wetsuit-legal swim, you need a suit that will slip through the water and won't weigh you down. On the bike, you want to be aerodynamic and limit drag-creating transitional ridges. On the run, you want to be chafe free. The skinsuit platform achieves all three. The Sanremo was constructed from SpeedFreak ventilated fabric up top and Instadry Speed fabric across the shorts. These form-fit fabrics are fast through the water and, once you are on the bike, dry quickly. Once dry, the Velocity mesh back not only has been proven as a watt-saver in the wind tunnel, it also helps to move moisture away from the skin to keep you dry and cool. The addition of a full-length camlock zipper also aids in cooling and ventilation by opening the top of the suit like a standard bike jersey, not to mention making pit stops during ultra-endurance races speedier. To minimize chafing, Castelli included the KISS Tri Seat Pad, a lightly padded insert that dries quickly after the swim. It's thick enough to support you during that 100-plus mile bike leg, but thin enough that you won't even feel it during the marathon. Additionally, the Free Sanremo suit is sewn with flatlock stitching and includes large back pockets to hold all of your race day nutrition.