What Our Gearhead(R) Experts Are Saying:"I reach for the Endurance 4 Bib Short when I know I'm in for a long ride. The Progetto X2 chamois is the most comfortable I've ever used-it's plush without feeling bulky. The mesh uppers breathe well and stay put, and the compressive fit gives my legs a nice boost over long climbs or tempo efforts."We count on the Endurance 4 Bib Short for long rides that push past comfort zones and into new mileage records. Castelli's premium Progetto X2 Air Seamless chamois is the star of the show, offering the kind of all-day support that makes century rides more enjoyable and recovery a little easier. The bibs fit close and move naturally, giving us a performance edge without sacrificing comfort. The Endurance Evolution fabric delivers compressive muscle support while managing moisture efficiently, so we stay dry and supported from first pedal stroke to final climb. Mesh straps and back panel keep airflow high, and GIRO3 leg grippers hold the cuffs in place without digging in. When we want to go far-and fast-these are the bibs we trust.