it involves a crossover and a lego piece (the piece has 2 axle pieces at a 90 degree angle and a hole in the center) and you put the lego piece on the same bar as the crossover
it involves a crossover and a lego piece (the piece has 2 axle pieces at a 90 degree angle and a hole in the center) and you put the lego piece on the same bar as the crossover