If you are looking for this specific "part3.rar" to fix an installation error (like a "CRC failed" or "unexpected end of archive" message):
: Part 3 of a multi-part RAR archive, typically used to split large game installers for easier downloading. Common Solutions for Download Issues Layers.of.Fear.2.PROPER-CODEX.part3.rar
: Layers of Fear 2 (a psychological horror game by Bloober Team ). Release Group : CODEX. If you are looking for this specific "part3