cPanel's backup compression method

I noticed that when cPanel does a full backup using tar compression, I'm able to open/view the archive without extracting it (in Windows). However, when I compress a directory myself using tar -cvf, it forces me to extract the contents before viewing it.

What command(s) is cPanel using to create/compress the directories into a tar?

I apologize if this is basic Linux/cPanel knowledge.

 

I accidentally left off the -z (for gzip) in my original post and actually have tried with that option, but still have the problem. After running that command and downloading the .tar file, when I open it in Windows with something like 7zip, I see a file within it simply named the same as the .tar file but without the .tar extension. Why don't I see the folder/file structure as I do with a cPanel-generated backup?