SPACERAIL 4 level, 26000mm rail Multiple tracks create extreme variety and a mesmerizing set Battery powered elevator for a endless marble runs - No need for a wall outlet Build time of 5-10 hours for lots of marble run fun with kids and adults (great for building with your kids!) Tons of cool stunts for extreme marble run ball coaster fun Have fun while learning principles of physics and engineering wiht this great STEM toy and marble run game