Product name:ComNav T300 gnss rtk Contellation:GPS, GLONASS, BeiDou, SBAS Static accuracy:2.5mm +0.5ppm, 5mm+0.5ppm RTK accuracy:8mm+1ppm, 15mm + 1ppm Channel:256 channels Internal momery:8GB Application:Topographic survey, engineering survey, Marine survey Special features:256 channels Beidou B3 Show More