Paris Air Show 2013: Two-seat JF-17 model
The FG defense team noticed this model of a two-seat Chengdu JF-17 fighter, though it looks like it also has fatter spine aft of the cockpit. The engine nozzle also looks different from the Klimov RD-93, so this model would probably be equipped with the Guizhou WS-13 turbofan. Our Asia expert Greg Waldron will have more on this later--assuming the Chinese feel like talking (and they often do).
Source:
http://www.flightglobal.com/blogs/the-dewline//2013/06/paris-2013-two-seat-jf-17-mode.html