Screws right on any car, truck, bike, motorcycle, RV, tractor, UTV, spaceship (Unconfirmed), or go karts tire valve stem cap. Great for pranking poorly parked cars who choose to ruin everyones day by parking their Kia Soul diagonally as if they drive with their eyes closed. Doesn't affect tire balance. Works on many different tires (car, truck, bike, motorcycle, etc). Easy and Fast Install. Keep in your cupholder for quick on the go pranking at school, work, home, public parking lots, tire stores, or even your moms house (we might've beat you to it, we were there earlier)...