Wooden Puzzle Roller Coaster, Ball Coaster Brand new, unassembled. The third and subsequent photos are of a completed one for my own use (assembly time: about 40 minutes). Here are some points to note when assembling: ① Because it's made of wood, it can break if you use too much force. ② Sandpaper is included, but it's easier to build with nippers and a design knife. ③ Some parts are tight, so it's recommended to remove burrs and adjust with sandpaper. Thank you.