As a breakthrough innovation, VC2 Plus Master is a smart charger that has countdown timer for each bay showing the time it needs to fully charge the battery. It can recognize, charge, and display both Ni-MH and Li-ion batteries at the same time and you can totally control the charging speed (0.5A/1.0A) as you like. In order to save time, the USB Output with Power-Path Management System enables you to charge both batteries and the external device at the same time while power is connected! - See more at: http://www.xtar.cc/products_detail/productId=63.html#sthash.IumSORfg.dpufJILI Charger - Backup Battery Charging Case for JUULJILI Charger - Backup Battery Charging Case for JUUL