The Sokkia GRX3 is smaller, lighter, and packed with the most advanced GNSS technology in a design built to withstand the harshest field environments. All signals, all satellites and all constellations ? in a compact, rugged design, with an integrated IMU and eCompass. Sokkia Tilt Technology Incorporates a revolutionary 9-axis inertial measurement unit (IMU) and ultra-compact eCompass, which compensate for mis-leveling up to 15 degrees. Sokkia Tilt Technology L Band Ready Technology 226 Universal Tracking Channels (Sokkia GPS, GLONASS, Galileo, BeiDou, IRNSS, QZSS, SBAS) Integrated 400 MHz UHF and SiteCom? radios Fusion Positioning? technology