The Fuji X100S eats batteries at a fair rate, so having a few extras is almost a must. However, the original batteries cost enough to suspect that they’re made half of gold. There really is no reason to pay that much when these (and other) third-party manufacturers can provide equivalent products way cheaper. I have three of these and they work just as well as the original that came with the camera. If you’re wondering about the number on it: I number all my batteries so I can keep track of which ones I’ve used, so they all get used the same amount.