Back Cover -- 6" wide x 4" high *Z = spine thickness calculated by dividing the total number of localized pages by 512. Once spine thickness is calculated and adjusted accordingly, the front and back covers need to be pulled in to attach to the spine for printing. Front Cover -- 6" wide x 4" high *Spine -- .5" x 4" hp hp color LaserJet 9500n color LaserJet 9500hdn http://www.hp.com C8546-90984 *C8546-90984* *C8546-90984*