When I received my charger I was surprised at how small and compact it is - little more than two DJI Mini 2 batteries side by side. However, the small size offers full performance in terms of charging options and batteries. I immediately connected one of my batteries and it started charging within seconds. The LEDs are also straight forward (Red is charging, Blue is fully charged). I like that you can store the batteries in the charger when not in use. Charging (there is a power switch to turn on the battery pack function), so it takes up a bit more space in my backpack than 2 batteries separately. I have a Costco combo pack with a smaller carry case and it fits easily in the back compartment with 2 batteries installed. The battery function works perfectly - I plugged my iPhone charger into a USB-B socket, turned it on and it started charging my phone straight away. You'll need to provide your own USB-C cable and charging box to use the charger, but for now I think everyone has at least a few. Great product, love the size and simplicity. !