Even without the heater on, these pants are warm! They are a shiny athletic style material. Nice and thick with good quality seams. The battery pack is at the hip, which is a tough spot, fit wise, but they're are a limited amount of spots it can go and I'm sure this is one of the better spots. The battery is long lasting and easy to charge with a usbc charger. I'm surprised how warm the leggings get with the heat at the knees. It's a nice gentle warmth. I was a bit between sizes and decided to go up instead of down because I hate tight pants. These bunch a bit at the ankles because I'm short but overall I'm happy with the fit (5'4" 140 lbs). I am someone who is always cold so I'll be using these leggings under dresses and tunics this winter.