Extended License
Extended License allows use of the item in one single end product, which you or one client may sell to end users (charge end users to access or use the end product), but user do not have access to the source files in any case.
Important: Distribution of source files is not permitted.
Extended license allows you, with the permission from Gautam Thapar (Author), to integrate Buttons X into your WordPress theme to sell on ThemeForest.
In order to read more about Extended license please visit CodeCanyon.