Model:Trimble r8 RTK GNSS surveying systems Satellite Galileo, and BeiDou (COMPASS) Channels:440 (RTK)Real Time Kinematics Horizontal:8 mm + 1 ppm RMS (RTK)Real Time Kinematics Vertical:15mm + 1ppm RMS Internal radio range:3-5km typical 10km optimal Initialization time:typically