Generally, every individual seat position (except for the last ones at the rear of the cabin) has a small set of auxiliary controls built into the seat back for the passenger directly behind the seat. The seat itself normally contains a small flip-out, extendable tray table (which must be folded away during takeoff and landing), and, on most wide-body international aircraft, an LCD video screen directly above the tray table (earlier aircraft had a single large projection screen at the front of each cabin). Directly above the seat (on the cabin ceiling) is a console for the passenger service unit.