A file named GEMELAS.7z is a created using the 7-Zip format. The name "Gemelas" is Spanish for "twins" (specifically female twins).
: It could simply be a folder of photos or documents related to twins that someone has compressed to save space or share more easily. How to Open the File GEMELAS.7z
To access the contents, you will need an archive manager that supports the .7z extension: A file named GEMELAS