M on an auction sheet: Modified
M (改造) means: The car has aftermarket modifications. The inspector writes it on the car diagram on the part it applies to, normally without a size number.
On the car diagram
MModified改造
The car has aftermarket modifications.
Watch out: Modifications can affect compliance and insurance. Check the notes for what was changed.
Other damage codes
A ScratchU DentB Dent with scratchW Repair waveS RustC CorrosionX Needs replacementXX ReplacedP Paint faultH Paint fadeY Tear or holeE DimplesG Stone chip (glass)R Repaired crackRX Repaired, needs replacingK ChipT Trim / other
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