large .. measures 25.25" long, 13.25" wide at the wide ends, 15.25" tall (fully extended), 9.75" tall (when only using the first height), 2.25" tall when fulled collapsed .. attached slanted tray for laptop has 3 adjustable angles, and tabs that flip out to keep the laptop from slipping down into your lap.. 4 usb ports in the back (not sure what for), also looks like there is a charging port (not sure what for), as I must of thrown out the directions with the box.. mouse pad on left and right.. cup holder indent on left side..heavy plastic.. patent #ZL200930165572.5 & ZL200920131662.7.. no flaws noted..smoke free home.