This is a 275mm x 100mm x 65mm tray. I use two strips of 1 in 3m VHB tape on the top and bottom of the back to attach the tray to the back of a vanity door. Also included are three different sized mounting tabs (30mm, 50mm and 50mm reinforced) that you can use if the double-sided tape won't handle the load. I use a cyanoacrylate (Super Glue) to attach the tabs.