Ukulele String Knob, Full Set Professional Ukulele Knobs Stable for Ukulele Adjustment Specification: Features: 1. Made of metal material, durable and long service life. 2. Great and excellent workmanship, easy to use. 3. There are two left knobs and two right knobs for using. 4. Replace the old and dirty , very suitable for ukulele adjustment. 5. This is a accessory for ukulele, it's very useful. Specification: Material: Metal Color: Silver Size: as picture shown Package List: 4 x String Knobs 8 x Screw