BTW, I probably have at least $2500 in all the stupid cones, pin plates, 3 jaw chuck, and other adaptors to balance all of the different combinations. And then somebody, like GM comes up with a bolt pattern never used before. Never a standard center bore either. Plus all of the different wheel weights. Endless problems that most shops can't deal with. No more, just hammer on just couple weights on a steel 15 inch wheel, and done. I have spent a lot of time shifting weights an 1/8th of an inch to dial them down to less than the weight of one rock pebble when I balance a tire. Sometimes it might take a dozen spins to get it close. Probably why my small customer base won't go anywhere else. I can't even begin how many times, what should be a simple tire install turns into a nightmare, even with the right equipment. Forget the bubble balancer, and the HF tire changer.