Credit cards to hold out in photo (7)

I believe the answer is:

plastic

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'credit cards' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for plastic that I've seen before include "Credit card - pliable" , "Synthetic substance" , "Credit card; mouldable" , "Compliant" , "means of deferring payment" .)

I've seen this clue in The Telegraph, The Times and The Sun.

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