Build the derby car of your derams with the SUPER BLOCK X 127: The body block is the foundation of any blazing fast car and Derby Champ's features holes drilled for perfect rear weight placement using our Slotted Tungsten Round (product #716) Weight fit perfectly into the large center hole.  and precision drilled axle holes for an extended wheelbase with 3 wheels on the track. Perfect or those who want to race with 3 wheels on the track (fastest) or use a Rail Rider(TM) alignment. For 4 wheels touching, we recomend the SUPER BLOCK X 125. Wheels and axles are sold separately to give your car that winning edge!