Type 1 - Deep Cavity. Works great for loose powder and also for pellets as long as you are careful and do not crush the pellets.
Type 2 - Flat with a very small and shallow cavity in the middle. This one seems to create more problems with crud rings. Eliminates crushed pellet potential.
Type 3 - Flat with a bigger and deeper cavity in the middle. Suppose to help with the elimination of the crud ring. Eliminates crushed pellet potential.
My Encore has Type 1 and it works fine with pellets and loose.