Castelli Cold Days 2nd Layer Base Layer 2.0

At the heart of the Castelli Cold Days 2nd Layer Base Layer 2.0 is Polartec® Alpha® 90 high-loft active insulation fabric, made sustainably from recycled PET. While initially tested as a direct-to-skin layer, Castelli discovered its true superpower lay in mid-layer performance. When paired over a technical sweat-wicking base layer (like the Castelli Prosecco), it creates a microclimate that delivers maximum breathability and warmth, eliminating the wet, clammy feeling that ruins sub-freezing bike rides.

Streamlined Design for Maximum Performance

Every detail of the Cold Days 2nd Layer 2.0 has been meticulously considered to give confidence on long, challenging winter miles. It features an intelligent half-length asymmetrical zip, mounted slightly off-centre to avoid a bulky stack of multiple zippers at your neck. Combined with a protective high collar and a close-to-body fit, it offers a versatile choice to tuck it neatly into your tights or wear it out. It's a beautifully tailored, pro-level solution that ensures you stay warm, dry, and focused on the ride.