Code 4307 applies to employers engaged in bookbinding.

Prior to the binding process, the printed pages are folded into units known as signatures with the use of buckle or knife folders or in some cases both depending on the weight of the pages.  This signature process is done so that the pages will be in proper position and order.  The folded signatures are then bundled together on power, pneumatic or bundling presses and assembled either manually or mechanically.  The signatures are bound together using wire staplers or adhesive or sewn together with thread.  The pages may need to be cut to final size which may be done with the use of guillotine cutters or knife trimmers.  The book will then be pressed to reduce its thickness.

Book backings and liners are glued using cold or hot glue and then assembled to form a completed book.  The book is then pressed on a removable or standing press until such time the glue has dried.  In some cases, pages are edged with gold leaf or rough edged.  The completed books are inspected, packed and shipped to the employer’s customers.

This classification also includes book repair in shop or restoring old damaged books.