Features performance sock with integrated heating element you don’t notice heating elements of the latest generation which completely incorporate the toe area the natural material mix of merino wool & silk supports the excellent heat effect of the sock optimal moisture transportation ergonomically knitted additional shin protector padding on the exposed parts ring bandages for optimum support on the foot the lithium packs are easy to attach by means of press studs on the legband machine washable at 30 °C light lithium packs fit all models of Lenz heat socks, heat vest, heat bandage & LED system attach lithium pack to legband of the sock via press studs heat can be regulated via 3 settings on the lithium pack heat can be continuously regulated remotely via smartphone (Bluetooth smart ready) heat development for up to 14 hours global USB (Universal Serial Bus)-charger with charging display short charging time flexible plastic case Package content 2 lithium pack rc B 1200 (rechargeable) 1 global USB (Universal Serial Bus)-charger 100-240 V 1 USB (Universal Serial Bus) charging cable with charging indicator 1 pair of Lenz heat socks 5.0