The StarFire™ 7000 Receiver offers a new correction level with accuracy like RTK Radio. The SF-RTK correction level provides 2.5-cm (1-in.) horizontal accuracy without the need for additional hardware. This is an improvement of 17 percent from the previous generation of StarFire receiver with SF3. The SF-RTK signal uses two additional satellite constellations (BeiDou and Galileo) as well as both GPS (United States) and GLONASS (Russia) satellites.