The tremolo arm features 6mm arm diameter, 9mm threaded collar internal diameter, it is designed for Floyd Rose tremolo bridge, with this arm, you can quickly adjust the string tension and change the tone, realize tremolo effects. Features: Tremolo arm for electric guitar, special for Floyd Rose tremolo bridge. 6mm arm diameter, 9mm threaded collar internal diameter. Made of high quality iron, high glossiness. Arm length approx. 175mm. It helps you to easily adjust the tension of string and change the tone. Specifications: Materials: Metal Color: Black Arm Length: Approx. 175mm Arm Diameter: Approx. 6mm Arm Internal Thread: 9mm Item Weight: 46g / 1.6oz Package Size: 18 * 3 * 1cm / 7.1 * 1.2 * 0.4in Package Weight: 47g / 1.7oz Package List: 1 * Tremolo Arm Note: Please measure your size exactly and check the size shown in picture carefully. The bridge not included.