The .7z extension signifies a highly compressed archive created with 7-Zip. This is common in the emulation community because:
If this is the Battlezone 98 Redux , simply run the .exe . Battlezone.7z
If you’ve recently come across a file, you’re holding a digital piece of gaming history. Whether you're a veteran of the 80s arcades or a newcomer exploring the roots of the first-person shooter (FPS), this 7-Zip archive is your gateway to one of the most influential titles ever made. What is Battlezone? Battlezone.7z
If it's an arcade ROM, you’ll need an emulator like MAME. Battlezone.7z
It shrinks large ROM sets or disc images into manageable sizes.