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article; goods; product
fine thing; fellow; affair; stuff
「代物」 has another reading with different meanings.
substitute
これはなかなかの代物しろものだ。
This is quite an article.
安いやすい代物しろものは壊れこわれやすい。
Cheap goods break easily.
見みた目めは地味じみだが中身なかみは本物ほんものの代物しろものだった。
It looked plain, but the contents were the real deal.