Wire binding is a popular commercial book binding method, and is known by a number of different names including twin loop wire, wire-o, double loop wire, double-o, ring wire and wirebind. With this binding method, punched pages are inserted onto a "C" shaped spine and then a wire closer squeezes the spine until it is round. Documents that are bound with wire binding will open completely flat on a desk and allow for 360 degree rotation of bound pages. Variations of this type of binding are Half Canadian Binding and Full Canadian Binding, these two styles provide for a wrap around spine. Dependant on the product thickness, there are 3 punch pitches that are used, 4-1" 3-1" and 2-1"