Having run into the cost of the factory Nikon batteries I've tried several off brands to see which ones were actually worth the money. Vivitar is by far, heads and tails above the rest. I've tried the fake Nikon Chinese made ones which at best perform for maybe a few months. The Vivitar's hold a much longer charge at 2500mAh than even the factory ones and don't believe the "if you use a different brand battery it will void your warranty" either! Not true! Automakers tried that in the 70's and we found out otherwise. Best battery for your money and will last a lot longer than the factory ones!