Crossword Genius

To free drill, beg for costly spanner? (4,6)

Ross

I believe the answer is:

toll bridge

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'costly spanner?' is the definition.
The definition suggests a singular noun which matches the answer.

'to free drill beg' is the wordplay.
'free' indicates an anagram.
'drill'+'beg'='drillbeg'
'drillbeg' with letters rearranged gives 'llbridge'.
'to'+'llbridge'='TOLL-BRIDGE'

'for' is the link.

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