Models make fun of highs (4-3)

I believe the answer is:

mock-ups

'models' is the definition.
(mock-up is a kind of model)

'make fun of highs' is the wordplay.
'make fun of' becomes 'mock' (I've seen this before).
'highs' becomes 'ups' (I've seen this before).
'mock'+'ups'='MOCK-UPS'

(Another definition for mock-ups that I've seen is " Full-size dummy models".)

I've seen this clue in The Telegraph.

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