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Engineered for aerodynamics and WorldTour racing performance. The careful choice of fabrics and components and the obsessive attention to detail make this bibshort supremely comfortable even when you don't pin on a number.
Meticulous Evolution
The Free Aero Race 4 Bibshort is our top race short, which also means that it's insanely comfortable even if you never pin on a number. The original Free Aero Race Bibshort was first introduced over a decade ago and has logged literally millions of kilometers under the backsides of our sponsored pro riders and has been the best-selling short both in the Castelli retail collection and in our Servizio Corse custom program. Over this time the short has undergone numerous updates and improvements in the never-ending quest to create the best short we can make.
While the basic concept of a minimalist workhorse pro-level comfortable race short remains, every single fabric, component, stitch and construction method has been updated and improved over time. The fourth major generation of the short features the updated Progetto X2 Air Seamless seat pad. This pad separates a soft, stretchy skin care layer that moves with your body from a generously padded cushioning layer that replicates the form of your saddle.
Eight-hour rides are no problem. Of course the fabrics are premium, made to our specifications by Italy's best fabric suppliers. The Forza fabric on the inner leg features 38% Lycra® content for perfect fit, while the Vortex fabric on the side panels is dimpled for aerodynamics. And it's held in place by the latest iteration of our seamless flat Giro leg gripper.
Features
- Vortex dimpled fabric on legs for aero performance
- Forza fabric on inner legs with 38% Lycra® content for perfect fit
- Stripe mesh engineered minimalist bib construction keeps you cool
- Giro4 leg gripper elastic for better grip distributed over larger area
- Doppio V construction in front for increased support and comfort
- Flat-lock stitching
- Progetto X2 Air Seamless seat pad
- Temperature: 15°-35°C / 59°-95°F
- Weight: 254 g
- Fit: Aero
- Material: Main Fabric: 62% Polyamide, 38% Elastane Sides; Lower Back: 79% Polyamide, 21% Elastane; Bibs: 94% Polyester, 6% Elastane; Lower Legs: 63% Polyamide, 37% Elastane; Back: 74% Polyamide, 26% Elastane
Technology
Progetto X² Air Seamless
Maximum Technology For Supreme Comfort. Constructed in two components, each dedicated to a specific purpose, that together create the most comfortable seat pad on the planet.Skin Care LayerSeamless, bacteriostatic layer made to adapt to the shape of your body and saddle without any folds in the fabric. Cushioning LayerSeamless Integrated Technology (S.I.T.) Perforated Viscous Comfort Zone.
Rosso Corsa
Our Rosso Corsa label is only applied to the highest-level products we make. Every thread and fiber, every curve and contour is obsessed about. Rosso Corsa represents a categorical breakthrough in cycling innovation and the meticulous craftsmanship you expect from Castelli’s Performance-Enhancing Apparel.