About this item Powerd by Solar Panel OR Battery : Build your own marble run by battery or solar, Connect wire of motor with solar panel if will use it under sunlight;Connect wire of motor with battery case if you are indoor. Requires 2 AA batteries (batteries is not included in the package),Wooden STEM toy is pure entertainment meets learning. Educational wooden mechanical puzzles :3D wooden puzzle marble run set is designed to teach children hands on skills like coordination, physics, STEM principles .they are suit for kids of all ages from 8 up to teens.Our DIY Model kits are also suit for adults who love challenge . High Quality:STEM Projects Science Experiments makes by premium basswood plywood. Non-toxic,No burr, marble track made safe from laser precision cutting.Perfect 3D wooden building Toys for kids ags 8-10-12-14. Perfect Craft gift :Our Jigsaw Puzzle is great gift for a birthday or chrismas,Theyare not only toys, but also craft art, which can be placed at home as decorations. You can give it to your children, husband, couple, wife. After Sales Service: 3-D wooden educational toys are designed to make children smarter, more imaginative and creative. Your child's safety and your satisfaction are our pursuit. For this toy, you will receive 100% customer support. If there are any quality issues regarding , we will provide you with a replacement or a full refund.