Ueasy Rechargeable Heated Insoles Li-ion Battery Rechargeable Heated Insole Outdoor Keep Feet Warm for Men (One Pair) Material: Li-ion battery, Nano leather material, Carbon fiber, Poliyou, Mesh fabric et. The heated insole fits for your shoes or boots 6.5-10(USA/Canada)/39~44(China) Li-ion battery capacity: 1800mAH/PCS, Charging time: 2.5H, When charging is completed, the indicator light will turns green. Battery life: 3-5 hours Intelligent temperature control, adjustable to three temperature settings to warm cold feet: 1)High temperature shift, LED light flash quickly 2)Medium temperature shift, LED light flash slowly 3)Low temperature shift, LED light all the time Press the switch button for 3 seconds, LED light off, without heating