Travellers going without support of boxers? (7)

I believe the answer is:

packers

'boxers?' is the definition.
(I know this)

'travellers going without support' is the wordplay.
'travellers' becomes 'backpackers' (people travelling with backpacks).
'going without' suggests deleting specific letters.
'support' becomes 'back' (to back is to support or endorse).
'backpackers' with 'back' taken out is 'PACKERS'.

'of' is the link.

I've seen this clue in The Guardian.

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