This specific 3D model, "Brick Mailbox Low-poly 3D model get", is an asset made available by "Unknown author".
You can download this asset for free at "Unknown platform" by following the link.
Usage of this 3d asset is subject to the "Unknown license" agreement.
OBJ (OBJ, filesize: 129 KB), FBX (Autodesk FBX, filesize: 89.2 KB), 3DS (3D Studio, filesize: 86.6 KB), MAX (Autodesk 3ds Max, filesize: 86 MB)