This product is a mini charger for 2 AA batteries. The kit comes with the charger and two AA batteries. You simply plug it into the wall and it charges the batteries. This is great for things like remote controls, computer mouses, etc. Those items that need batteries every once and a while. The packaging claims that the batteries last up to a year...so I'll have to see. Bought the item as way of saving batteries from ending up in the dump. It was on special for $7.99 less a $5.00 manufacturer's coupon at Shoppers.