Overview: 100% new design and high quality Men's fashion items Warm winter goods Specifications: Size: S / M / L / XL / XXL / XXXL / XXXXL Operating temperature range: About -5 ° C to 40 ° C Fabric: Polyester Color: Black, royal blue, camouflage, red The long sleeve has three heating zones,the vest has four heating zones， and the Special vest has two heating zones Package Content: 2x Fever vest Note：The difference between Special Blue and Blue is that different suppliers have different product quality. Special contains graphene. "special" is 2 zone heating