XT20 are for those who take flatness and straightness measurements for machine installations, and for those who check surface flatness on manufactured parts. XT20 is water and dust protected (IP55). This is the choice for maintenance and installation technicians. Excellent also for checking flange flatness.
XT22 in addition also lets you point the laser beam perpendicular to the laser plane. A built-in vertical precision level also lets you level it when mounted on its side so the laser plane sweeps vertically. XT22 provides more options for geometrical measurements, and even higher accuracy and precision thanks to fiber laser technology, among other things. With this transmitter you can literally measure anything!