Radiomaster ExpressLRS USB UART Flasher V2

  • $11.99
    Unit price per 


Upgrade your ELRS firmware with ease using our simple and effective tool. The new V2 version features a USB-C interface, enabling you to connect the tool to your PC via cable. The new power button allows effortless power cycling with a single press, eliminating the need to struggle with cables while holding down buttons. Our streamlined design makes preparing your receiver for a firmware update faster, easier, and more efficient than ever!

When it comes to updating your ELRS receivers, you're faced with two options: Wi-Fi or Serial Port. While Wi-Fi upgrading may seem convenient, it can be unreliable due to network instability. This can result in a bad flash, requiring recovery with a UART tool. That's where the V2 ExpressLRS USB UART Flasher comes in, offering a reliable and easy solution for your firmware upgrade needs.

With the RadioMaster V2 ExpressLRS USB UART Flasher, your wireless connection won't be a concern. This dongle is specifically designed for ELRSF receiver serial port upgrades, providing a reliable and easy solution for flashing or recovering receivers with a bad flash. 

Our USB flashing tool is a versatile solution, not limited to ELRS serial port upgrades. It comes with a range of connection options, allowing easy connection to our entire range of receivers. By switching between 3.3v and 5v, it can also be used for other devices requiring a UART interface. This versatility makes it a valuable addition to your toolkit, catering to all your firmware upgrade needs.

Radiomaster ExpressLRS USB UART Flasher V2


  • Upgraded USB-C interface
  • Power button for easy ON/OFF power cycling
  • Reverse polarity protection
  • Over-voltage protection 
  • Switchable power supply between 3.3V and 5V
  • Standard 2.54mm pins
  • RM-CRSF JST-GH port for simple plug-n-play connection with RadioMaster ER series receivers
  • Pin sockets included
  • Dupont cables for convenient testing
Radiomaster ExpressLRS USB UART Flasher V2

Compatible Receivers:

Using 2.54mm pin output and spring-loaded pin adapter or Test hook adapters:


Using regular 2.54mm pin output (Servo Plugs):

ER3C-i 2.4GHz ELRS PWM Receiver
ER5C-i 2.4GHz ELRS PWM Receiver
ER4 2.4GHz ELRS PWM Receiver
ER5A 2.4GHz PWM Receiver
ER5A V2 2.4GHz PWM Receiver
ER5C 2.4GHz PWM Receiver
ER5C V2 2.4GHz PWM Receiver
ER6G & ER6GV ELRS PWM Receiver

Please note: The second channel is repurposed as a TX for the serial port tool's RX port, while the third channel is repurposed as an RX connected to the serial port tool's TX port.

Firmware upgraded by RM-CRSF interface output:

ER6 2.4GHz ELRS PWM Receiver
ER8 2.4GHz ELRS PWM Receiver
ER8G & ER8GV ELRS PWM Receiver

Please note:  The above receivers can be connected to the receiver's CRSF port using a 4-wire CRSF cable.

Firmware Upgrade Instructions

  1. Connect the Serial Port Cable with the receiver
  2. Connect to the computer with a USB extension cable, press the receiver's BOOT button, then press the POWER button on the serial tool
  3. Follow the ELRS upgrade tool's instructions to complete the upgrade


Radiomaster ExpressLRS USB UART Flasher V2
Radiomaster ExpressLRS USB UART Flasher V2

1x Radiomaster ExpressLRS USB UART Flasher V2
1x Pogo Probe
1x CRSF Wire
1x 2.54mm Serial Port Cable - Type B
1x Serial Port Test Hook - White
1x Serial Port Test Hook - Green
1x Serial Port Test Hook - Red
1x Serial Port Test Hook - Black
1x User Card

Download USB to UART Driver

Download USB UART Tool Connection Guide

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