The HP LaserJet 75-Sheet Envelope Feeder in white (CE399A) is a printer accessory designed specifically for HP LaserJet printers. This feeder, with dimensions of 4.75 inches in height, 13 inches in length, and 9.25 inches in width, allows users to easily feed envelopes into their printers for efficient printing. With a unit quantity of 1, this genuine HP product ensures compatibility and reliability for seamless operation with HP LaserJet printers.