The 900MHz R9 MM-OTA receiver implements the ACCESS protocol and brings the user improved performance and features. The R9 MM-OTA supports wireless firmware updates over the air making binding to receivers even easier. As well as the convenience of checking the current receiver firmware version. The R9 MM’s compact form factor design is also carried over to the OTA version, and the R9 MM-OTA supports inverted S.Port as well. This receiver works compatible with the new release R9M Lite Pro module,and the other 900MHz modules will also be supported when the ACCESS firmware is available. SPECIFICATIONS Dimension: 16*10*2.8mm (L×W×H) Weight: 0.7g (without antenna) Number of Channels: Non-LBT Version: 4/16CH (Telemetry) LBT Version: 4/16CH (Telemetry) / 4/16CH (No Telemetry) Operating Voltage Range: DC 3.5V – 10V Operating Current: 100mA@5V Operating Range: Up to 10km or above Compatibility: R9M Lite/R9M/R9M 2019 with ACCST firmware; R9M Lite/R9M Lite Pro/R9M 2019 with ACCESS firmware FEATURES 915MHz (Non-LBT Version)/ 868MHz (LBT Version) Mini size and super lightweight Supports OTA firmware update Supports firmware version check S.Port enabled and support telemetry data transmission (Support F.Port, download firmware to support the function) Inverted S.Port enabled Low latency and high precision With RSSI output in SBUS Battery voltage detection supported Detachable Ipex connector antenna