TOSR121 - 2 Channel Smartphone Bluetooth Relay - (Password/Momentary/Latching)


Bluetooth Relays


156 In Stock

Regular price US$39.95
Delivery to USA, Canada, Australia, UK, Germany and Europe: 7-15 days
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NOTE: Though the video shows 4 channel relay, this product description is for 2 channel relay.

TOSR121 is a Bluetooth Relay kit that supports both Android and iOS and it has a  password set option. 

It is a convenient and easy-to-use product that be used to control any electrical types of equipment. You can pair up this device with a mobile phone or a computer. 

Open the APP->Connect Device, use your phone to search for a new Bluetooth device. The module will appear as "BT Bee-BLE"(iOS) or "BT Bee-EDR"(Android). Connect it and then you can control the relays turning it ON/OFF. The communication way also can be changed easily. Replace the Bluetooth Bee module with a Wi-FiBee, it becomes a Wi-Fi relay.

TOSR121 is an upgraded version of TOSR02. It supports password. It can be set to latching or momentary outputs

TOSR121 allows computer control switching of external devices by using the USB port of your computer. It also has a wireless extension port, it can work with Xbee or BluetoothBee or WiFibee module, so, you can control your device via ZigBee or Bluetooth or WiFi.

The TOSR121 provides four-volt free contact relay outputs with a current rating of up to 10Amp each. It comes with one DS18B20 temperature sensor port.

The module is powered using a 5V DC power supply (or USB). The DC input jack is 2.1mm with positive core polarity and the relays are SPDT types. If you want to power it with DC 12V or 24V, you just need a 12V/24V-5V DC Converter.

Note: Relay board default password is: 123456

Note: Please remove the Bluetooth module when you use USB control. 

Smartphone App:

We also provide FREE Android/iOS App. You can control your device by your phone very easily.



Android APP(Bluetooth)

iPhone APP (Bluetooth)


Relay power rating
If the relay is used at a voltage or current exceeding this specification, the life of the contacts may be significantly shortened.

A full datasheet for the relays used on the TOSR121 is here: G5LA datasheet

If you use DC power, the Input voltage should be DC 5V.

First Step - Install the Driver
The TOSR121 module uses FT232RL USB to UART chip. Before using the TOSR121 you will need to download the FT232RL Driver.

Connect the TOSR121 and windows will detect it and ask for the drivers. Point windows to the inf folder and it will install the driver.

The TOSR121 will now appear as a com port.

The TOSR121 operates with an easy to use command set as described in the table below.

TOSR121 Baud rate: 9600 

Test program
To get the TOSR121 up and running in the minimum amount of time we have put together an example program to demonstrate the functionality of the module.


  • Working voltage: 5V DC
  • Dimension: 89.5x45x17.2(mm)
  • Standby Current 10mA/5VDC
  • Current rating of up to 10 Amp.
  • Latching or momentary outputs
  • Password supported

Documents: Download all the files at once.

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