Combination binding machines make a lot of sense and prevent you from boxing in your company to use just one binding method. Combo binding machines allow you to choose what type of binding you want for a particular binding project, For example if you buy a plastic comb binding machine and then someone in the office decides a particular document at some pint in time would be better in wire you would have to buy a wire binding machine as well. With a combo machine you can choose between comb, wire and coil combinations depending on what type of combo binder you buy as they can bid either 2 or 3 combinations.