Special Notice: DEPT OF DEFENSE is procuring airframe structural components for the DEPT OF THE AIR FORCE. The service/item being procured is a flap track assembly, specifically NSNS: 1560-01-228-3678FJ and 1560-01-522-2407FJ P/N's: 160D611632-5 and 160D611632-6. A flap track assembly is typically used in aircraft to control the movement of flaps, which are movable surfaces on the wings that increase lift during takeoff and landing.