Features: Lock the helmet ,theft protective. Can rotate 360 degrees,Light weight and easy to install Suitable for: Motorcycle, electromobile, bicycle. Specifications: Color: Black Material: Nylon fiberglass+metal Size: Approx. 65*57 mm / 80 * 57mm Weight: 130g /150g Package List: 1 * Helmet Lock 2 * Key T6061 aluminum+plastic