What Our Gearhead(R) Experts Are Saying:"The Cold Days 2nd Layer Vest slotted perfectly into my layering system on a cold and windy morning in the low thirties. It added just enough warmth at the core without making my arms feel restricted, and at 128 grams, I barely noticed it was there until I realized I had not thought about being cold once during the ride."The Cold Days 2nd Layer Vest from Castelli takes the same Polartec Alpha insulation philosophy as the full Cold Days 2nd Baselayer and focuses it entirely on the core. Sleeveless construction keeps the arms free for full movement and ventilation, while the vest adds meaningful warmth at the chest and back where heat retention matters most. At 128 grams, it disappears into the layering system without adding bulk under a jacket.