I ordered this 2 pack of the K&F Concept 2400mAh NP-W235 Battery for my Fuji GFX100s.

When I take my GFX out for a full day of shooting, I have to take a boatload of extra batteries with me. The energy-hungry GFX uses the same low-capacity battery as the newer Fuji X-series cameras. I'm sure that the Fuji engineers chose to use this smaller battery (as compared to the battery found in the GFX50r) in order to reduce the size and weight of the 100s, but any advantage gained is, in my opinion, more than compensated for by the need to carry more batteries and a charger to charge them on.

These batteries don't need a charger. You just use the included USB-C to USB-A cord. The USB-C end plugs right into the battery and the USB-A end goes to your favorite charging block or your car's USB port. Honestly, it's a technology that deserves to be adopted by all of the camera manufacturers unless they want their clocks cleaned by the quality third-party battery distributors.

It's hard to directly compare the longevity of any battery with another, because every shoot is different. A shoot where I am using the LCD screen a lot is going to eat up battery power faster than when I rely only on the viewfinder. What I can say is that these batteries play nicely with the Fuji electronics. The camera throws no errors when using the K&F Concept batteries and properly reports their state of charge and capacity.