WOMEN'S MW GOLF SOFTSHELL VEST, SAPPHIRE BLUE, Medium 100% polyester; Machine wash cold water on gentle or delicate cycle, line dry, no bleach, do not tumble dry, do not wring out, do not dry clean Made of lightweight Windshark 4-way stretch, waterproof, breathable windproof fabric Optimum placement of three heating panels keeps the upper body muscles warm and loose 7.4V rechargeable lithium-ion battery provides up to 10 hours of comfortable warmth China