Dextrus :- Dye guns have a groove down the side to take a wire in between the top and the bottom half, Pm`s don`t have this groove because they use a ribbon, I think this is the only difference between the two guns, so take care when clamping the two halves together as it will chop the wires, you may as some , may not be able to screw the top and bottom together as tight as you would like just to accommodate this, best advice is to stick to a ribbon, again take care when putting the white end part into the board as if this bends it could break and this is where most ribbons go