The Toknav TSA500 is an external GNSS measurement antenna tracking six satellite constellations (GPS, GLONASS, BDS, Galileo, QZSS, SBAS) across eleven frequency bands for millimeter-level positioning accuracy. It measures roughly 152mm in diameter by 62mm tall, weighs about 500g, and carries an IP67 weatherproof rating for outdoor use. It's suited to land and marine surveying, dredging and channel measurement, and structural/landslide monitoring applications.