This specific 3D model, "Robotic Arm 3D model 21", is an asset made available by "Unknown author".
Can be downloaded at "Unknown platform" by following the link.
Usage of this 3d asset is subject to the "Unknown license" agreement.
MAX (Autodesk 3ds Max, filesize: 87.5 MB), OBJ (OBJ, filesize: 87.5 MB), FBX (Autodesk FBX, filesize: 87.5 MB)