The "GTA San Andreas Windows 88110 mouse fix" is a community-created modification (mod) rather than an official patch from Rockstar Games. It usually comes in a compressed archive (ZIP or RAR) containing a .cs script file (often named gta_sa.exe or a script placed in the scripts folder) or a .asi loader file.
: Corrects the aspect ratio so the image isn't stretched. gta san andreas windows 88110 mouse fixzip