``U.S. Extra No. 1'' consists of nectarines of one variety which are mature but not soft or overripe, which are well formed, clean, and free from decay, broken skins which are not healed, worms, worm holes and free from injury caused by split pit and free from damage caused by bruises, growth cracks, hail, sunburn, sprayburn, scab, bacterial spot, scale, scars, russeting, other disease, insects or mechanical or other means.
(a) At least 75 percent of the nectarines in any lot shall show some blushed or red color including therein at least 50 percent of the nectarines with not less than one-third of the fruit surface showing red color characteristic of the variety. (See Sec. 51.3150.)
(b) [Reserved]