Its a digital 3D Printable STL file especially designed for 3d Printers , is not a actual physical product !!
These STL files were modelled especially for 3d printing.
You are going to find 4 different templates in the attachments: 25° ,35°16, 45° and 60° each of them has 18 holes , which diameters varies from 10 to 60 mm.
They have 1,5 mm thickness with a 0,5x45° chamfer in the holes as the commercial Ellipse Templates have.
Printing setting :
0,1 mm layer thickness for better precision
i would recommend using transparent PLA filament