Features: -With two 4000mAh Li-polymer batteries, which can provide you with heat for up to 4-8 hours. -With 3 temperature setting function, includes High Temperature (149°F, 4-5 hours), Medium Temperature (131°F, 5-7 hours) and Low Temperature (113°F, 7- 8 hours) . -The heated socks are made of safety material. Breathable, quick-drying, specially designed flame retardant cotton makes you feel safer during use. More importantly, the far-infrared heating elements of the heated socks can stimulate blood circulation. -Washable, hand washable and machine washable, take out the battery before washing, put the socks into the laundry bag (to prevent the charging cable from being torn). .
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