This is a monster truck based on a semi truck. The cab vibrates realistically when you drive it over a bumpy surface. I built this because I love Monster Jam, but I didn't want to base the model on something lego would need a license to make. The front wheel are on rotation joints so they can be steered and the 2 sets of rear wheels can be hinged up and down. The driver is smart and really knows how to race a so large vehicle. I may start making official monster jam vehicles in the future, but I have several other ideas waiting.