From the model description:
A rotating spring lifts the train up the first hill, then releases the train, where it dives and rises into its second turn. The second hill provides enough potential energy for the train to continue smoothly around the loop and power it through its corkscrew. The kit consists of 464 pieces made of durable ABS and POM plastic. When fully assembled, it spans 4' 9" long by 15" wide and stands 25" tall.
Here's a link to the working scale roller coaster.