正膠有好幾種，有圓錐型的，有圓柱型的，還有圓台型的。有高度大於直徑的，有高度小於直徑的。

來源: 走資派還在走於 2021-04-07 18:35:39 [博客] [舊帖] [給我悄悄話] 本文已被閱讀：次

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