(2) Rechargable 3.7V Lithium batteries; lasts up to 10 hours on low, 3.5 hours on high; 80% cotton, 20% spandex heat trapping fabric; USB charging cable with dual chargers; heats up to 115°F.
(2) Rechargable 3.7V Lithium batteries; lasts up to 10 hours on low, 3.5 hours on high; 80% cotton, 20% spandex heat trapping fabric; USB charging cable with dual chargers; heats up to 115°F.