It is not really 20,000 mah power bank. I tested it 3000 mah battaray 3 times and 2700 mah battary charged 2 time .total approximately itis 15000 to 14000 mah power bank Product quality good But heavy weight
The worst product I have ever seen , its charging pin damaged my 3 mobiles, 1 Asus Selfie, 2nd Samsung J2 n 3rd Samsung GSM CDMA. I am unable to charge through charger after charging with the power bank. Hopeless, don't purchase this product.