This is a ultra thin heated vest for use under a jacket. It is machine washable. It has three settings low(104F), medium(122F) and high(141F). It dose come with the power pack which has two USB outlets and you can charge your phone with as well. Its made to fit snug so the heat is transferred to the body and not the air. It is made with good quality material. Battery last between 4-10 hours depending on setting.