You're referring to the PRF (Precision Rifle Folder) weapon!
"PRF weapon" is likely a misspelling of PRF (Platelet-Rich Fibrin) prf weapon
The arms race continues. The only way to future-proof your team is to constantly check the "Skill Inheritance" restrictions of new PRF weapons. Many new PRFs now include the line: "Only usable by [Unit Name]." This means no Inheritance—pure exclusivity. You're referring to the PRF (Precision Rifle Folder) weapon