This would be a product that I said well why not, not believing that they are that great.
I was wrong and am writing this review while wearing a pair.
I wear a size 12 and they fit very well. I could see a size 13 fitting nicely too.
There are 3 heat settings and I keep them on the lowest around the house - at first I had them on the hottest and they were HOT - thinking that will be great while snow blowing, but I digress.
I thought the battery was going to be clunky - nope, there is a very thick well made pocket for them.
I bought 3 pairs, so I am always wearing a pair with 2 sets of batteries charging.
Battery life is about what is stated about 10 hrs on low and less as you go up in heat settings.
**batteries REALLY DO take 6 hrs to charge, so if you have yours sitting and waiting for a big snowfall so you can use then outside, make sure you put them on the charger well ahead of time.