Flexible binder used extensively in offices (7,4)

I believe the answer is:

elastic band

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'flexible binder used extensively in offices' is the definition.
I can't judge whether this definition defines the answer.

'flexible binder' is the wordplay.
'flexible' becomes 'elastic' (similar in meaning).
'binder' becomes 'band' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'elastic'+'band'='ELASTIC BAND'

Can you help me to learn more?

(Other definitions for elastic band that I've seen before include "Loopy item" , "the papers may be gripped by?" , "Loop of thin rubber" , "Office item" , "Rubber ring" .)

I've seen this clue in The Globe and Mail.

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