- Thread starter
- #4,721
Well, I was close.No, I'll give it up. I got sent a box of freebie energy saving goodies from my power company and this is one of the things that was in there. Apparently it is a filter whistle. You clip it onto your furnace filter and it's supposed to whistle when the filter needs changing.
 
	 
 
		 
 
		 
			
		
		
		
	
	
			
		 
			
		
		
		
	
	
			
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		
 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		