Comix Plastic Comb Binding MachineSteel construction for strength and durability. Stainless steel dies resist rust. 4 level adjustable edge guide (2. 5 mm., 3. 5 mm., 4. 5 mm., and 5. 5 mm.) Document thickness comb guide helps user select proper comb width Number of Items : 1 each Product Specifications Binding Pattern : Plastic binding wire Punching Binding System : lever Number of Punching Binding Holes : 21