The Sanremo 4. 0 Speed Suit from Castelli brings together the comfort and aerodynamics of a speed suit with the long-mile functionality of a traditional kit. While most speed suits are limited to short criterium and time trial applications, the Sanremo 4. 0 extends its utility to almost any type of training ride or race. The top half of this dynamic duo is a jersey designed in the style of the Aero Race, which is constructed using Castelli's Velocity Rev2 fabric to usher airflow over your body as you ride. The bottom half of the suit is Castelli's popular Free Aero Race 4 Short, which is designed for aerodynamic racing and comfort during long, back-to-back rides. Castelli lines the suit with its top-of-the-line Progetto X2 Air chamois, featuring a luxuriously soft arrangement of multi-density foam strategically placed to provide support on 100-mile road races or 60-minute crits alike without inhibiting your movement in the saddle.