Perfectly sized for the Puffco Pro stock atomizer, and as fine tuned as can be for the system.
The differences between the 3 options for the bottom are minor, albeit important.
Red - Best flavor, fastest heatup, ideal function while heating element is on. Optimizes high terpene oil.
Yellow - Balance of flavor, heatup, and heat retention. Most balanced function.
Blue - Best heat retention. Best for larger dabs.