My husband works in Hvac. he installs furnaces in buildings that don’t have any heat and works in freezing cold conditions.He has tried wool socks, and thick, expensive work socks but nothing seems to keep his feet warm enough. So I decided to order him these heated socks..I only wish that I would’ve ordered them sooner.they are absolutely terrific!One charge can last him all day on low setting. On its highest setting it can get him to lunch time. So he can recharge with his power bank no problem.They charge up fast! About 30 minutes.Not only do they keep him warm but they also help with foot pain that he’s dealt with for years.The different heat settings really come in handy especially living in New England where the temperature fluctuates so often.Very nice quality fabric as well. thick, yet also breathable. padded for extra comfort and support.they also do very well in the wash. they keep their shape and no pilling whatsoever.. (I hang dry them)Overall extremely happy with these heated socks. totally worth the price tag! I would definitely buy them again.