Pair of horny males in coarse material (7)

I believe the answer is:

buckram

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'coarse material' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for buckram that I've seen before include "Coarse cotton fabric stiffened with glue" , "Stiffened open-weave fabric" , "Coarse stuff" , "stiff stuff!" , "Bookbinding material - cub mark (anag)" .)

I've seen this clue in The Times.

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