J20 two-seater version has surfaced

 

New Chinese belt-fed machine guns in 5.8x42 and in 7.62x51.

Both variants featuring extrude aluminum receivers with steel reinforcement. Long receiver design w/ short feed cover for reliable optic mount behind. The 5.8x42 version has a bottom magazine well like that of the Negev. The 7.62 version has a combined short recoiling and gas operation, but no mag well. They have been testing this at least since 2014.