The original payday 2 texture for flashlight is a low quality sprite that illuminates small area. I made this small mod to improve it. Now the area that are illuminated is much bigger and texture looks better. I sugest you use No Flashlight Glow Mod with this mod, it will look much better!
You don't need anything, just place the unpack folder in mod_overrides folder!
I use texture from "Re-Texture Project" with you can check up here