SuperSU Pro version is the latest development of apk SuperSU by Chainfire. Pro SuperSU is not a stand-alone app and first install SuperSU and then reboot device. Android SuperSU Pro adds the license file for SuperSU. It is just 2.99$ you have to pay for supersu pro download and install the file for your android system for a better performance.
Source: http://supersuapk.com/