Features: Bow Straighten Appliance can correct violin beginners’ wrong bow posture,which seems like a silent teacher always reminding you to maintain correct bow posture, and then develop good bow habits. Item type: Bow Straighten Appliance Material: Acrylic Color: As pictures. Occasion: musical instruments. Size: For 4/4, 3/4, 1/2, 1/4, 1/8 Violin. Package includes: 1*Bow Straighten Appliance Notes: 1. Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! 2. Please allow 1-3cm measuring deviation due to manual measurement.