Features: Self-locking training guide and helps you cultivate proper bending and wrist action. OOTDhe angle of the arc straightener can be adjusted by yourself. It is more convenient to practice for beginners. Durable and meticulous workmanship, lightweight for portable carrying. This simple orthosis is easy to use and has a remarkable effect, making the doctor pay more attention to rhythm and intonation. Specification: Material: PlasticWeight: Approx. 60gColor: As the picture shows Size: Approx. 100x5 0mm/3.94x1.97 inchesPackage Included: 1 x Violin CollimatorNote: Please allow 1-2cm errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item.