Shopping Cart
When you see a file ending in , it means it is the third piece of a larger split archive. The mention of a "solid feature" (Solid Compression) is a specific method used by 7-Zip to improve the compression ratio. Understanding Solid Compression
It significantly reduces the size of the archive, especially when compressing many similar files.
Since this is part 3 of a set, you cannot open it by itself. To extract the contents:
Use 7-Zip or WinRAR to open only the .001 file.