Drugs of unusual quality in the 60s? (4)

I believe the answer is:

gear

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'drugs' is the definition.
(I have seen 'illegal drugs' mean 'gear' so perhaps 'drugs' could also mean 'gear')

I can't explain the rest of the clue.

Can you help me to learn more?

(Other definitions for gear that I've seen before include "Clothes - equipment - first to fifth in a car?" , "Toothed wheel that interlocks with another" , "Toothed wheel used when changing speed" , "Unusually good" , "Trendy clothes - changed in car?" .)

I've seen this clue in The Telegraph.

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