The Police Officer’s Field Guide was custom designed with Chicago Police Officers in mind, however the book is also very handy for suburban and other police agencies. Much of the books content is cross compatible with other Departments. The field guide features durable laminated covers with color coded sections for easier access to content, and a pliable spiral binding that allows it to be folded and to remain open and readable, no snags or ripped clothing. The book was designed to fit in the breast pocket of your vest carrier or in your cargo pant pocket, may not fit in some female vest carriers. The field guide has a 15/16″ outside diameter spiral binding.