Eccentric lecturer has a security device (4,6)

I believe the answer is:

card reader

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'a security device' is the definition.
The definition suggests a singular noun which matches the answer.

'eccentric lecturer' is the wordplay.
'eccentric' becomes 'card' (card can mean an eccentric person).
'lecturer' becomes 'reader' (synonyms).
'card'+'reader'='CARD READER'

'has' is the link.

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I've seen this clue in The Daily Express.

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