Part of clock checked when wound back, slow (4,5)

I believe the answer is:

dial plate

'part of clock' is the definition.
(section on a clock)

'checked when wound back slow' is the wordplay.
'checked' becomes 'plaid' (plaid is a checked pattern).
'when wound back' says the letters should be written backwards.
'slow' becomes 'late' (I've seen this in other clues).
'plaid' written backwards gives 'dialp'.
'dialp'+'late'='DIAL-PLATE'

I've seen this clue in The Guardian.

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