The Swix Triac Alpha Vest is a versatile training vest that can be used during warm up, to keep warm before and after the activity or just as a leasure vest. Polartec© AlphaTM is a lightweight, ventilating insulation material, used on the inside for extra warmth and breathability. The vest is made up of a combination of thin and windproof outer fabric and an elastic fabric on the back and sides for excellent mobility - made for athletes or those seeking supreme performance for competition and training