$4.99 Set of grates plate 3D model by Davidjgere. Available on CGTrader with 38725 polys and 36636 vertices. Check it out on CGHub.
C4D (Cinema 4D, filesize: 3.67 MB), OBJ (OBJ, filesize: 4.97 MB), FBX (Autodesk FBX, filesize: 1.12 MB), DAE (Collada, filesize: 3.2 MB), 3DS (3D Studio, filesize: 2.51 MB), STL (Stereolithography, filesize: 3.57 MB)