I have a couple dozen cartos in circulation at any given time.  I have abbreviated all of my flavors.  I write on my black cartos with a silver sharpie, and I write on my silver cartos with a black sharpie.  Then a tiny piece of scotch tape to cover it so it doesn't rub off.  It hardly shows.  I also put black sharpie dots near the end of my eGo batts right next to the eGo lettering to denote 1, 2, 3, etc...and a tiny piece of tape so I can keep them in an even rotation.  It's not even noticeable.
	
		
			
		
		
	
			
			
				
		
			
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