This thermometer sensor that is sold under the Digitech brand, it can be purchased separately. Or can be found with XC0321 and XC0322.
It communicates over 433.920 MHz that can be read by RTL_433.
- The Crystal frequency is around 32kHz
- There's and LED on the board, but quite useless as its covered in the case and a waste of power, it flashes when its sending data
- There is also another area on the board LED2 but its not populated
- The device weighs 27g without batteries.