1Durable and Reliable: Made of premium metal, these electric guitar string retainers are built to last and provide a secure locking mechanism for your strings. 2Easy to Install: These roller can be easily installed on the head of your electric guitar, providing a quick solution to keep your strings in tune. 3Enhanced String Stability: These locks prevent your guitar strings from slipping out of tune, ensuring that you can play with accuracy and maintain consistent intonation. 4Smooth Locking: The locks offer a smooth and secure locking action, allowing you to confidently perform bends, vibrato, and other guitar techniques without worrying about string slippage. 5Universal Compatibility: These locks are suitable for use with most electric guitars, providing a versatile locking solution that can be used with various string and head designs. 2 xGuitar String Retainer 2 x Screw