It's the first time I've used such a special charger, I think it's really brilliant. It is well built and is a box with a snap closure. Inside you can put 4 Sony or 4 Canon batteries or 2 Sony and 2 Canon batteries. Charging is fast and balances the batteries so that they are all charged evenly so they are ready together, it doesn't heat up much and has a socket to circulate air. The button is very convenient to see the battery status from the outside at any time. The interesting thing is that it is a 3 in 1 product: it is a quadruple charger, a container for batteries and acts as a powerbank, in fact, in addition to the USB-C port to start charging the batteries, there is a USB-A and a Type-C socket to connect a phone, a tablet, a flash or anything that can be recharged via USB. In addition, with 4 batteries inside, you have a total charge of almost 10,000 milliamps, more than enough for any electronic device that does not absorb too much current in terms of volts. It can practically be transformed into an emergency powerbank. It also has 4 places to store memory cards. I have never seen such a product and I can say that it is useful, comfortable and super versatile. Finally I have a place to store my batteries, recharge them and if necessary I can use their charge for something that I forgot to recharge and during their time as a videomaker or photographer it unfortunately happens often. It's just a pity that they don't make a 6- or 8-seater version.