The Lenz Body heat system warms the body from head to toe. The lithium pack rcB 1800 can be used for all models of the Lenz heated socks, heated vest, heated bandage, heated gloves, heated pants and the LED system. The lithium packs are connected with push buttons. The lithium packs are small, light and provide up to 20 hours of heat at the touch of a button at work, sports and leisure. This increases the ability to perform and concentrate, even in cold temperatures, and ensures that blood circulation is maintained. The lithium packs rcB 1800 can be controlled directly on the lithium pack. With the Lenz heat app, however, the heat can also be regulated continuously via smartphone. Optimal when the lithium packs are under several layers of clothing. Package Contents 2 lithium pack rcB 1800 (rechargeable) 1 USB charging cable with charging indicator