Incra ULTRA24SYS 24-Inch Jig Ultra Woodworking System Woodworking system for most serious woodworker as well as beginners Tune your position precisely with an incredible 1/1000-inch increment Ultra glides on a three-point self-lubricating and self-cleaning linear bearing system Patented sawtooth racks position your work in exact 1/32-inch steps Lifetime warranty on the rack; 1-year warranty on all other parts