The utility model has convenient use and firm fixing and is an efficient auxiliary appliance for protecting books.

它使用方便、固定牢靠，是保护书刊的一种有效的辅助用具。

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The utility model has convenient use and firm fixing and is an efficient auxiliary appliance for protecting books.

它使用方便、固定牢靠，是保护书刊的一种有效的辅助用具。

youdao