I bought it for my son who is a cyclist, a real one. He usually takes 2 to 3 months away cycling more than 2,000 miles abroad. This is the second time I buy this same power Bank brand to him. I don’t know much about it but it must be great for his trips. It’s kind of heavy in my opinion for a person who carries along 4 saddlebags on his bike to survive far from home. Anyway the product must be good.