Two items for the toolbox obtained at the chemist's (8)

I believe the answer is:

nailfile

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'two' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.

I can't explain the rest of the clue.

Can you help me to learn more?

(Other definitions for nailfile that I've seen before include "Manicure item" , "Manicurist's tool" .)

I've seen this clue in the Evening Standard.

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