The Lenz Body heat system protects the body from cooling in the critical areas. The lithium pack rcB 1200 can be used to operate Lenz heated socks, heated vest, heated bandage, heated gloves, heated pants and the LED system. The batteries are easily fixed by push buttons. The compact lithium packs warm the body where the body is particularly vulnerable to cold. The heating power can be controlled directly on the lithium pack or by means of the free smartphone app. Lenz USB Lithium Pack RCB 1200 | Christy Sports