“U.S. No. 3” consists of grapefruit which meet the following requirements:
    
    
    
    
        
        (2) 
         Similar varietal characteristics;
     
    
    
        
        (4) 
         May be slightly spongy;
     
    
        
        (5) 
         May have rough texture;
     
    
        
        (6) 
         Not seriously lumpy or cracked; and,
     
    
        
        (7) 
         May be poorly colored.
     
    
        
        (i) 
         Not more than 25 percent of the surface may be of a solid dark green color.
     
    
    
    
    
    
        
        (c) 
         Not very seriously damaged by any other cause.
     
    
        
        (d) 
         For tolerances see  § 51.628.