The battery lasted a total of 1 hour 24 minutes and 43 seconds filming at 4K 30FPS on a 100% full battery with no screen saver and brightness at 100% Turn oSimply plug the 30pin cable into your GoPro® 3 or 4 Connect the other end of the cable to a USB 5V power source (must be at least 2A supply, not an iPhone charger or computer output!) and you're in business; That also means 30 A/h It is about 6 inches long by 4inches wide by 3/4 inch deep It does a good job of charging devices but for time lapse it is a fizzer, the reason being that once you plug it into the GoPro through the side entry of the skeleton case, it begins to charge the internal battery
How Long Does Gopro Battery Last