Switch Army Knife (SAK) is a versatile "all-in-one" utility that allows users to:

Essentially a copy of your prod.keys file but renamed with a different extension. SAK often requires this specific filename in its bin folder to function correctly. How to Resolve "Missing Keys" Errors in SAK

No, publicly distributed "prodkeys" are not correct, legitimate, or safe for long-term use.

By 2021, many "SAK" releases were re-packaged by other uploaders, often including outdated .keysdat files that no longer worked with newer software versions (e.g., Vegas Pro 18 or 19).

For almost every operation—especially decompressing NSZ to NSP or converting XCI to NSP—SAK requires a set of encryption keys. These are usually contained in a file named prod.keys or keys.dat .

In 2021, filed multiple DMCA takedowns against repositories hosting SAK-style .keysdat files for Vegas Pro. Similarly, the BSA (Business Software Alliance) reported that 37% of "cracked prodkeys" shared online contained either ransomware or spyware.

It is a source of keys itself. Rather, SAK is a tool used to dump (extract) the keys from your own personal Switch console. If you have a modded Switch, you run SAK, and it generates the prod.keys and title.keys files that you then copy to your PC.