Hootoo HT-TM05 TripMate User Manual page 76

Click Device to view the TripMate information
Serial number: it refers to which batch your TripMate belongs to,
which is the same as that S/N labeled on the bottom of your TripMate.
When you have some problems with your TirpMate, providing the serial
number to our Tech Support will help to solve the issues.
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