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1·Backing up key files is about a combination of identifying the files and finding a suitable method for storing and backing up that information.

备份关键文件涉及到确定相关文件，并找到一种合适的方法存储和备份这些信息。

2·Used either solely as Rough Pumps, or in combination with other high vacuum pumps as Backing Pumps.

可单独作低真空泵用，也可与其他高真空泵组合作前级泵用；