Ready, set, BUILD the track of your dreams with Hot Wheels Track Builder Unlimited. The Track Builder Unlimited Curve Kicker Pack is a part of the BOOST category and adds momentum to turn at any angle The Curve Kicker is adjustable and goes from a U-turn to a 180-degrees to add 'oomph' to your tracks. The Curve Kicker Pack is one of 7 different packs that lets kids BUILD, STUNT, and BOOST. The BOOST category gives kids an innovative stunt piece they can add to their Track Builder Unlimited world. Connects to other Hot Wheels sets (sold separately) for infinite possibilities. Add to other packs in the BUILD and STUNT categories for even more fun or add this stunt to Multi-Lane Speed Box or Triple Loop Kit (sold separately). Great gift idea for ages 6 to 10 years old.