When ever you buy a power bank you should know 5 things about that power bank
1st-The main artibute to a power bank is it’s capacity , the capacity is measured in milli ampler hour which is also known as(mAH), you should buy according to your usage if you use your mobile or any other device for a long while you should buy a higher mAh power bank a 1000 mAh pb can give you charge for 3 times
2nd- USB charging should be quite good and not fluctuating you need to see both the outputs of pb and input of your device which have to be same
3rd- You should not buy a portable power bank which eitheruses furbished batteries which is harmful and also not long time working
4th- portability easy to handle movable light in weight ease of access this are the qualities which a power bank have in
5th-powerbank recomendation to best charge your phone or your device