Plastic coil spiral binding is run through a series of closely spaced holes near the gutter margin of loose pre-collated sheets. There are multiple colors, size and pitch options for plastic coil and the resulting book product is crushproof, durable, has a clean modern look, and is very economical. This binding style is very useful when your needs require a book to lay flat, take heavy usage, and also open back to make copies. Popular option for planners, manuals, notebooks, study guides, journals and other note taking type books. The flexibility of the binding itself makes it very convenient.