Description: Music Box is motored by remontoir,not need the battery. The Principle of the Music Box is release of the spring in with remontoir, turn the gear and drive the Sound cylinder. Many bumps on the Sound cylinder, and then it will play the wonderful music ringtone when turning. Main Material: Zinc Alloy + Plastic ABS Machine Movement Size: 45 X 33 X 15mm/1.77 X 1.3 X 0.59" Music Melody: Random Music Use Scope: Can be as the baby toy, ornament, craft, gift, etc. Package included: 1 x Music Box Keychain 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 1-3mm measuring deviation due to manual measurement.