This specific 3D model, "Gas mask helmet 3d model scifi Low-poly Low-poly 3D model 139", is an asset made available by "Unknown author".
You can download this asset for free at "Unknown platform" by following the link.
The license for this digital asset is "Unknown license".
MAX (Autodesk 3ds Max, filesize: 890 KB), OBJ (OBJ, filesize: 383 KB), FBX (Autodesk FBX, filesize: 191 KB)