AGS (Auto-grip system) yoke fits instruments with a neck width up to 2" Instant push-button height-adjustment allows for easy changes on the fly N.I.N.A. (Narrow Instrument Neck Adjustment) accessory accommodates your ukulele, mandolin, banjo, violin, and more SFF (Specially Formulated Foam) rubber contact points safeguard your instrument from damage High-friction rubber feet provide excellent stability