Product was purchased for hunting and was ordered one size bigger to go over layers at a 2XL. I have a lot of hunting clothing and all my vests and jackets are 2XL and fit with room for movement. This vest with just a thin shirt on is at least 20 inches from coming together to zip it up. Fit is note even close.Battery that came with it lasts about 2 hours, but my own usb battery pack lasts around 8 hours even in minus temperature. Nice vest fits snug but keeps u warm. Ive had it about two weeks so not sure of durability or how it holds up being washed. Ill update review in a few months.Es de buen materia , aún si activar los calefactores es bastante cálido, las zonas que más calienta es el cuello y la espalda , no tanto al frente , para mi peso y estatura pedí el tamaño L , si recomiendo que compren este producto .It joes a good job of providing heat for a long time. You need to order at least the next size up, still a little snug.My bother assumed it would fit with the size we purchased. He said it was really sungvery light weight and really good for outdoor activites . if you are a person who like outdoor activity it will be a good investment. l recomend it. the size run small so consider ordering one size bigger than your jacket sizeMy husband was very excited about getting this product when he opened it for Christmas. He is a solid size L. The size L was WAYYY TOO SMALL for him. But the buyer insisted that he just needed an XL. So we returned the L and got the XL. With the XL, it is still snug. And the arms are small. He can wear it, but he is concerned it will restrict his movement in his line of work. We are debating about returning the XL. I would not buy, unless like I said, you go 2 sizes larger.Bought for hubby at Christmas. The heater in the truck is acting up. He loves it. Actually wears it and charges it without reminders. Although I did remind him that he still has to get the heater fixed.