The Golisi S4 Smart Battery Charger is there best one yet! The HD LCD bright blue Liquid Crystalline display tells you the percentage charged, voltage, current and the time until charging is complete. It tells you the charging mode you’re using and the type of battery. It gives the voltage input and so much more. The S4 charges most rechargeable batteries from 32mm to 70mm in length and 32mm in diameter. It is able to determine what type of battery has been placed in its docks and charge it according to that particular battery’s needs. The 2A slot offers lighting fast charging for when you need a battery charged in a hurry. Smart polarity prevention works well with the S4 charger. The body of the Golisi S4 is made with fireproof ABS+PC material and the springs and contact plates are military grade stainless steel and should last 100k cycles. There is a full suite of protections working at all times. With the S4 Smart Battery Charger by Golisi you can even charge different batteries sizes and chemistries at the same time!