If you are looking for legitimate ways to interact with hitboxes or manage your FiveM installation safely, use these primary sources:

Rockstar and FiveM both include features. When you verify your game files, the system checks for any modifications and restores original files if changes are detected. This is mentioned in the mod's description—if you want to revert to normal models, you can "do a verification of the game files".

To protect yourself from malicious downloads:

While FiveM generally allows client-side mods, certain modifications that provide a massive competitive advantage can trigger hardware ID (HWID) bans if flagged by the global anti-cheat system.

Even if a file manages to bypass FiveM’s global anti-cheat, modern roleplay (RP) and player-versus-player (PvP) servers utilize custom, server-side anti-cheat scripts. These scripts detect unnatural hit registration patterns. Getting caught results in a permanent community ban and a spot on shared server blacklists. How to Safely Find and Verify FiveM Files

Safe, verified visual plugins belong strictly within the plugins folder inside your FiveM Application Data directory. Server Rules, Ethics, and Fair Play

Drop the downloaded x64a.rpf into your directory, replacing the default file.

for the current year.

This is a modification that increases the size of player head hitboxes, making headshots easier to hit. It is often used in PvP scenarios, but it is highly controversial and often considered cheating on most competitive RP servers.

A practical example (hypothetical)