The Hand Grip Height Adjuster is easy to operate. A locking pin secures the stand at your desired height. Specially Formulated Foam rubber is used on all the contact points between the stand and your instrument. Designed not to harm your instruments finish, SFF rubber is tested as lacquer-safe. The Auto Grab System is made up of a center yoke and two arms. Driven by the weight of your guitar or bass, the arms rotate down when you put your instrument on the stand and open up as you lift it off. Designed to withstand repeated use, the AGS is coated with SFF.