PMD Products Magnetic Camber Caster King Pin Gauge Automobile Car Truck Wheel Alignment Tool Mounts onto a hub or brake disc for quick and accurate measurement of camber & castor angles. Also does king pin inclination On the rear there are two brass adjuster knobs, one to zero the bubble during angle measurement and the other for adjusting the king pin inclination. The Camber gauge has fixed graduation from +5 to -5 The Adjustable castor gauge is graduated from +11 to -3. The King pin gauge is graduated from 0 to 14 left to right.