Lightweight thermal efficiency. Engineered for high performance with reduced weight, the Sierra Thermal Vest offers lightweight warmth and windproof protection. Featuring Stormtech Thermal Shell™ insulation and a DWR water-repellent finish, this vest keeps you warm and dry while shielding you from the wind. The Thermal Shell™ Insulation ensures optimal core warmth, and the windproof outer shell adds an extra layer of protection against the elements. Perfect for layering, this vest is your go-to piece for warmth and performance in cold, unpredictable weather.