Magical Multi-functional Toy: The 3D gravity puzzle is great for intelligence development, hands & eyes coordination and balance, spatial cognition, focus, observes ability and patience training. Help to improve player's space imaginative ability, memory.^ Great Fun to Play Anywhere: About 10cm in diameter, easy to carry anywhere. Best desk toy for stimulating inspiration, relieving stress. Also good for parents-children games, party games, killing time.. This brain puzzles are interesting for people who love brain games, it's also a nice gift for your kids friends family colleague.^ Safe to Use: This Labyrinth Brain teaser maze puzzles is made of ABS non-toxic plastic material, burr free, and the tiny steel ball is confined to the transparent protective cover, safe 3D maze puzzle toys for children to play. This classic puzzle game will never go out of style.^ Suitable for the Crowd: Suitable for kids, adults and the older. In order to increase the level of difficulty, please note that the channels and little steel ball in the highest difficulty level maze ball are narrow and small. For the elder people and little kids, you can choose the red color or orange color, more easy to play 3D maze ball.^ Four Different Challenge Levels to Choose: The red color for easy level, the orange color for medium level, the blue color for hard level, and the green color for highest level. There are two kinds of Steel Balls inside the Maze, the Steel Ball inside the red maze (easy level) and orange maze (medium level)are 4 mm in diameter, and 2 mm diameter inside the blue maze (hard level) and green maze (highest level).