Saddle stitch staplers or simply
saddle staplers are
bookbinding tools designed to insert staples into the spine (saddle) of folded printed matter such as
booklets,
catalogues,
brochures, and
manuals. They are distinguished by their unusual length (most traditional staplers are too short to staple booklets easily) and by the presence of a V-shaped hump or "saddle" which is used to precisely align the central fold of the material to be stapled.