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だ。
This is quite an article.
安い代物は壊れやすい。
Cheap goods break easily.
見た目は地味だが中身は本物の代物だった。
It looked plain, but the contents were the real deal.