The sizes M2, M3, M3.5, M4, M5, M6, M8, M10, M12 come with 1" OD split screw adjustable die button.
The sizes M6 x 0.75, M7 x 0.75, M8 X 0,75, M9 X 0.75, M11 X 0.75, M12 X 0.75 come with 1" OD round die button (non-split)
The sizes M14, M16, M18, M20 come with 1 1/2" (38mm) OD split screw adjustable die button.
The sizes M22, M24, M25, M30 come with 2" OD split screw adjustable die button.