IKN Chrome Metal Guitar Strap Buttons Lock End Pins Strap Lock w/Mounting Screws for Electric Acoustic Guitar, Bass, Ukulele,Pack of 4 Locking strap buttons for acoustic guitar, classical guitar, electric guitar, bass or ukulele. It is a small metal made end pin with rubber washer. Screw: about 0.87in/2.2cm long. Material: Metal,Color:Chrome. Package Include: 4pcs guitar end pins.