BS100B EZ-Glide Music Stand.  The EZ angle roller with special frictioning rubber holds the desk at the desired angle.  Equipped with a clutchless grip for easy height adjustment.  The inner locking mechanism secures the desk at the desired height.  To adjust the clutchless grip, push the upper shaft until a yellow switch appears at the base of the shaft.  Twist, one click at a time: clockwise to loosen and anti-clockwise to tighten.  Desk size: 21"x11.5".  Height 27.1"-48.4".  Weight 3.2lbs.