Feel the electricity run through your body with the KNEX Thrill Rides Electric Inferno Roller Coaster Building Set! Using the 639 KNEX parts and pieces including rods, connectors, and track create this electric inferno that sends the coaster car hurtling through the twists and turns. Then, download exclusive instructions to build an incredible second model. Ideal for builders aged 9 to 14 years old. Requires 2 x AA batteries (not included).