The Frankford Arsenal Platinum Series Perfect Seat Hand Primer will make sure you do not over seat and crush a primer again. It features a dial that adjusts the seating depth .001 at a time with a total adjustment range of .05. Once you have the seating depth set, you can squeeze the handle as hard as you want; with the positive hard stop the primer will never seat deeper than the set depth. The Frankford Arsenal Perfect Seat Hand Primer, designed so you can have the perfect primer seat every time. It comes with 12 shellholders (#1, #2, #3, #4, #5, #7, #8, #9, #10, #11, #12, #19) which will cover 652 calibers and a heavy duty injection molded storage case so you never lose a part and the Hand Primer is always protected. The primer tray holds 100 primers for quick seating of multiple cases and works with small and large primers.