if its $21.99 let me be very clear on this
IT IS VERY LIKELY NO 20,000 MAH !!!
I seriously question if that battery is even 10,000 mah maybe 12,000 (and even then it won't be $22)
be very careful. on a lot of things like this they flat out LIE about actual capacity.
has anyone actually tested capacity in one of these? how many charges did you get and from "what level" if discharge on your phone?
2 charges from say 50% taking it down to 75% is not saying a lot for its capacity