Yes, carto screws on fine.  As an example, my other batts all light up when the button is pushed, whether a carto is on them or not..   the light on this one now only comes on "sometimes"... as I said, more often NOT than does.  At first I thought maybe the button was getting stuck, as I had that happen on my PT once.. but thats not the case here.  Possibly the switch in the button is going out.. ??   Thanks, dohsma, for trying to help me.   I did remember I had tossed a reg batt into my bag the other day just in case... Thank goodness, I have that to puff on!   
	
		
			
		
		
	
			
			 
				
		 
 
		 
 
		
 
 
		 
 
		 
 
		 
 
		