Images have emerged this week of the
1) The J-10B has an infrared search and track (IRST) system on the right side in front of the cockpit.
2) The J-10B has a slightly larger vertical stablizer with a rounder edge.
3) The J-10B's engine exhaust duct is slightly shorter in relation to the tail.
4) The J-10A has struts between the engine intake and fuselage.
The J-10B's engine intake is flush with the fuselage, for a smoother, cleaner
Blow are more pictures of the J-10B, and one with the J-10B alongside the J-20.