Universal Compatibility: This Guitar Training Aid is designed to fit most acoustic guitars, specifically those sized 38inch and 41inch. Beginner-Friendly Features: Addressing common beginner challenges, this tool aids with string tension, sound accuracy, and reduces finger fatigue. for Guitar Enthusiasts: Whether it's for a teenager or an adult, this guitar auxiliary tool serves as an excellent gift for anyone passionate about learning guitar. Effortless Installation: Easily attach this learning aid to your guitar's neck in just a few minutes. The clip-on design simplifies the setup process, allowing you to start practicing without the need for complicated tools or extensive setup time. Enhanced Learning Efficiency: By assisting in the correct positioning of hands and improving muscle memory, this Guitar Electric System significantly boosts learning efficiency. Color:As Shown Material:Plastic+Metal Package Contents: 1 * Chord Machine Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.