These tools are designed to aid and simplify setting up front and rear suspension geometry. Sold as a pair. A real time saver for the person that works on their car alone. Bolt to each front hub, rotate the hubs until the tools are at 0° horizontally, use the notches in the tools to measure your toe and adjust tie rods. Rotate the tools vertically and use a small magnetic angle finder to accurately set your camber. Bolt the tools to your rear hubs to accurately measure rear axle location when building rear suspension. The uses are endless. Tools fit almost any 5 lug bolt pattern up to 5x5.5” with 1/2” and 5/8” studs. 4” ID clears large hubs of factory and aftermarket spindles.