The downloadable file is original. It has not been modified in any way.
File: aoclsetup-15.0.0.145-windows.exe Size: 191 MB MD5: 0f3d1d7359948ea8bbe146a8412a8a3f Last checked: October 6, 2023.
PhysX SDK is proprietary, multi-platform, realtime physics engine middleware.
Nice tool to view and analyze HL 3D models.
It adds documentation, sample code, header and library file.