PowerDriver 4 Bay Slot Smart Power Battery Charger Fast Battery Charger for 9V Lithium Rechargeable Battery with LED Indicator Specifically designed for 9V Lithum battery, no Alkaline or Carbond one-time use 9V battery is allowed This charger can charge 1~4 pcs 9V li-ion battery according to your requirement Smart LED indicator shows charging status:Blue(Charging),Off(Fully Charged) The battery charger uses the MCU control technology, providing the constant current & constant voltage safety model Using environmentally friendly materials,sturdy, security, light, portable, and long-time span The charger is just for indoor use ,keep it away from moist and heat