No more struggling with mounting those snap-on tires, this tool makes the job easy. Universal to work with 8", 20", 22", and 24" wheels. One stem will go through the center bearing of the wheel. The wheel will spin on this stem. The bearing fit will not necessarily be a tight fit on the stem. The stem is only used to rotate the wheel. The other stem will go between the wheel rim and the tire being mounted. This stem will draw the tire onto the wheel rim with ease while rotating the wheel.