Feature: 1. Battery Powered: 18 note musical mechanism movement is powered by 2 AA batteries (batteries not included) for ease of use. 2. Therapeutic Function: Musical mechanism movement has a therapeutic function, just play the core on the desktop, watch its gears turn and listen to the pure tunes, very interesting. 3. DIY: Music box mechanism can be installed in a cardboard box, wooden box, glass box, plastic box, metal box, you can create a unique octave box. 4. Acrylic and Alloy: Music box mechanism is made of acrylic and alloy, which is not easy to damage and can be used for a long time. 5. Perfect Gift: Musical mechanism movement is a perfect gift for your friends, family and colleagues for Christmas, Thanksgiving, etc. I believe they will love it. Specification: Item Type: 18 Note Musical Mechanism Movement Material: Acrylic, Alloy Product Use: Suitable for Birthday Gifts, Musical Enlightenment, Etc. Batteries: 2 AA Batteries (Battery Not Included). Package List: 1 x Battery Box1 x Movement4 x Screws