Receieved this product as a part of the Amazon Vine program to test our and review, these are my honest thoughts. Historically, I've always been very pleased with K and F Concept products. I own numerous lens filters, and camera bags by K and F. I was excited to test out the portable charger for Sony NP-FZ100 batteries. I own and use a Sony A7iii and it's always handy to have a portable charger/holder in your camera bag along with extra batteries. As all K and F products the the packaging was well presented, and the build quality was excellent. I immediately tested out the charger - which connects to your power source via USB-C - on my two A7iii batteries. They fit snugly and immediately started charging. The charger has a power display which shows how full the batteries are charged which is handy. The holding tray doubles as a carrying case to which the batteries themselves snap in and stay inserted. You remove the tray by pressing a button and sliding it off the charging base unit. The charger also included a soft, lovely leather bag intended for carrying the instructions to which I will likely use to carry lens filters. K and F always seems to send extra bonus items with their products such as cleaning clothes and in this case a premium feeling bag. I am very happy with this case/charger combo. I think the only way to improve upon it would be for the unit to double as a power supply and carry a charge internally for on the go charging. However, if you travel or go to shoots with a power bank you can plug this in and carry it in your backpack, car, or camera bag without any issues.