The subject line of an email landing in your inbox reads simply: .

He clicked .

The file is a compressed archive containing a Qualcomm Calibration Network (QCN) backup specifically for the 128GB variant of the POCO X4 Pro 5G Go to product viewer dialog for this item. (code-named "veux"). File Purpose

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The file extension for . This is a compressed archive. Compared to .zip or .rar , .7z offers superior compression. The poco x4 pro 5g 128gb qcn tested.7z file is typically between 150KB and 2MB compressed, but once extracted, it may contain a .qcn or .bin file of around 5-10MB.