These little battery banks pack a powerful charge. I tested them on my phone as that's where most of my battery banks are used and by comparison this exceeds my expectations. Being so small I didn't expect them to hold up but I got a 50% charge over a couple hours, while heavily using my phone.
These units are light weight and small. The design is nice. For what they are I would call them cute.
Simple to use, just plug them in to charge. Comes with a short charging cable.