Steel yourself for the excitement of the race with the new K'Nex Steel Scorpion Coaster. Build a classic roller coaster that's over three feet tall using over 1,000 K'Nex pieces, featuring a motorized chain lift, a speaker to work with your MP3 player, And over 28 feet of twisting, turning, looping track for an authentic roller coaster experience. Go to KNex.com to download instructions to build the double dip roller coaster. Imagine. Build. Play. K'Nex Steel Scorpion Coaster. Batteries not included.