The TSA520 is a rugged external GNSS antenna that tracks GPS, GLONASS, BDS, and Galileo (plus QZSS/SBAS/IRNSS) across their full frequency bands, making it suitable for RTK base/rover setups. It measures about 152mm in diameter by 62mm tall, weighs roughly 400g, and carries an IP67 rating for dust and water resistance. It's intended for land, marine, and construction surveying tasks such as dredging, bridge and landslide monitoring, and precision agriculture.