Fasteners one has for outside padlocks (5)

I believe the answer is:

hasps

'fasteners' is the definition.
(hasp is a kind of fastener)

'one has for outside padlocks' is the wordplay.
'for' means one lot of letters go next to another.
'outside' suggests removing the centre (I've seen 'outside of' mean this).
'padlocks' with its centre removed is 'ps'.
'has'+'ps'='HASPS'

I've seen this clue in the Evening Standard.

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