Castelli

Frequently Asked Questions

• How does the Alpha RoS 2 jacket perform in winter conditions, and what are its standout features?

  The Alpha RoS 2 pairs a fleece inner with a Gore‑Tex Infinium outer for warm, wind‑resistant protection on cold rides, with dual layers tuned for insulation and breathability. It includes glove‑compatible cuffs, three rear pockets with drainage, and racing‑oriented tailoring to balance weather protection and on‑bike mobility.
• Which Castelli bib shorts or tights are best for hot‑weather racing versus long endurance rides?

  For hot weather, Superleggera bib shorts use the lightest, most open fabrics and aggressive Lycra cuts for maximum breathability and minimal weight. For long endurance days choose Endurance bibs with Endurance Evolution fabrics and the KISS Air2 pad for extra comfort and moisture management; Progetto X2 Air sits between them if you want race performance with added padding and airflow.
• How should I size Castelli's race‑fit bib shorts and jerseys for the best balance of aerodynamics and comfort?

  Castelli runs a race‑ready, anatomic cut with high compression—many pieces use GIRO³ leg bands and mesh bib straps—so expect a snug fit; sizes commonly span S–3XL. If you ride long hours or prefer more freedom, consider sizing up one size for extra comfort, but keep your intended use in mind (racing vs training) when choosing the tighter race fit.
• How do the Progetto X2 Air bib shorts compare to Nano Flex Pro 2 bib tights for wet and cold conditions?

  The Progetto X2 Air bib shorts focus on all‑condition performance with the Progetto X2 pad, progressive damping and airflow perforations for ventilation and comfort in warmer or mixed conditions. Nano Flex Pro 2 bib tights use Nano Flex DWR and waterproof shin guards with a seamless pad for specifically wet, cold rides where water repellency and thermal protection are priorities.