What are charging specs?

[cr500taco]

charging specs

Does anybody know what the charging specs are? I want to get an external battery bank for it and want to make sure I get one that will be fast enough. Been looking at Anker batteries and they have 2 kinds. One is a 2A output and the other is 4A.
I have a Verizon Jetpack that doubles as a charger, but it charges the tablet pretty slow.

 

[FF22]

Re: charging specs

I would try matching the specs of the charger it came with. But I'm not an electrical engineer and don't know if 4A adds anything or might damage the unit.