Are you looking for the simplest method to merge multiple PDF files in one PDF? Install and open CubexSoft PDF Merge Tool https://www.cubexsoft.com/pdf-merge/and load the PDF files by utilizing dual options i.e. Select File(s) or Select Folder(s). And also allows users to save the resultant file in the desired location path. It provides the demo version that permits to merge first 5 PDF files with watermark for free. Need to combine thousands of PDF files for an urgent presentation, buy its licensed version. 

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