,𝐋𝐎𝐍𝐆-𝐋𝐀𝐒𝐓𝐈𝐍𝐆 𝐔𝐏𝐆𝐑𝐀𝐃𝐄𝐃 𝐁𝐀𝐓𝐓𝐄𝐑𝐘: Autocastle heated socks with 7.4V 2200mah large capacity battery,Autocastle battery-heated socks can last up to 4 hours on highest setting and 10 hours on lowest heat setting, so no need to worry about the power running out too soon.
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