The last one has the "green cup" attached to it.  That is the "outer race" and is actually the axle shaft that fits into the front axle housing.  I didn't look too closely at the first two, but they do seem to be similar.  Maybe they are different lengths?  I know that there are a couple of threads rolling around here regarding the front axle shafts and their associated part numbers.
				
			 
			
		 
			
				
			
			
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