GPS SBAS is a satellite sensor that utilizes the signals coming from the Global Positioning System (GPS) satellite constellation and satellite-based augmentation systems (SBAS).  Wide Area Augmentation System (WAAS) is one example of SBAS.  It also supports EGNOS, MSAS and GAGAN to the extent that they are compatible with WAAS.

They are GPS sensor units designed to meet the requirements of US FAA TSO C145c and intended for installation on board civil aircraft.  Their primary function is to provide aircraft position, aircraft velocity and precise time.

Part numbers 21000 and 21001 share a common mechanical enclosure. Both have a TNC-type antenna connector and a 25 pin D-type connector for all other input/output. Part number 21000 supports the RS-232 based NexNav Binary and NMEA 0183 interface protocols. Part number 21001 supports the RS-232-based Accord Binary and NMEA 0183 interface protocols. Both are authorized US FAA TSO C145C, WAAS Class Beta 1.  All NexNav mini sensor units meet the requirements of US FAA Advisory Circular 20-165B for ADS-B GPS source.