Stand - Professional - Wheel Truing - Digital Includes two digital indicators to true side-to-side and up-down simultaneously*no more guesswork, Lightweight, yet rigid, aluminum frame and axel fits wheels from 16* - 21* with 20 mm - 30 mm axles, Threaded cones on axle keep wheel more secure than cones with index screws, Stand's base has adjustable rubber feet to maintain level axle, Flexible mounts fix indicators exactly where needed, Professional truing stand for more precise results