Features: 1.RELAXING EFFECT: This music box movement offers therapeutic features for kids and adults, watching the little gears move and listening to the music is delightful and stress relieving. 2.MUSIC BOX DIY: You can install the movement into DIY boxes, such as paper boxes, wooden boxes, glass boxes, plastic boxes and metal boxes, and you can make your own music box. 3.EASY TO USE: The sound power of this wind up music box movement is generated by a spring, just turn it and release it. 4.BATTERY POWERED: The Clockwork music box movement frees up your hands and is battery powered for quick and easy use. 5.HOLIDAY GIFT: Music box mechanism is the perfect Christmas, Thanksgiving, birthday, etc. gift to kids and adults who love crafts. specification:Item Type: 18 Note Musical Mechanism Movement Material: Acrylic, Alloy Product Use: Suitable for Birthday Gifts, Musical Enlightenment, Etc. Battery: 1 AA Battery (Battery Not Included) Size: Approx. 5 x 4.5 x 2.3cm / 2.0 x 1.8 x 0.9in PackageList: 1 xBatteryBox 1 x MusicalMechanismMovement 4 xScrew NoteManual measurement, there may be slight errors