No confusion. I use WWAA hulls for spreaders, and STS hulls for 'standard' loads. Simple as red and green.

You could of course use something like the silly Nitro-27 gold hulls for your nickel plated and buffered super duper thumpers if you wanted to...

The all yellow 20ga does present a small problem, you do have to look closer to see which shell is which...

"The price of good shotgunnery is constant practice" - Fred Kimble