If you want to access the QR code of your Check'In, know that it is also on the box.
If you wish to access the IMEI of your sensor, this can be found in the Check'In application in the Information tab then Advanced information.
To remove Check'In from its support, remove the SafeStick from the middle slot to place it in the top slot of the Check'In.
You can use the tip of a paperclip or the tip of a pen to help you do this.
Here is the video procedure: