"Pilots, Man Your Planes!"   
                                         WWII U.S. Naval Aviation Collector's Guide                                                                              
AN-6530 Goggles
Above:  The Navy contract AN-6530 goggles in their boxes of issue. Charles Fischer Spring on the left, contract number NXS-321, and American Optical, contract number NXS-1562, on the right. Gray cushions and  straps are provided with each.

Below:  The goggle broken down into its main components. Frame, cushion, strap and lenses.
Below:  A comparison of the upper vents. From front to rear, American Optical , C.F.S. later production with brazed vents, C.F.S. early production with riveted vents and the C.F.S. MK-II goggle with riveted vents as used on their early production AN-6530s. We can also see the change in shape to the C.F.S. vent opening, as mentioned previously.

Note the satin finish of the AN-6530 frame as opposed to the brightly polished finish on the MK-II. 
All face cushions and their retainer bands had three top and three bottom vent holes for the left and right eye opening, which made them compatible with either American Optical or Charles Fischer Spring frames.