The file 'Telescope Alignment Tool Adapter 3D Printer Model' is (stl) file type, size is 356.1KB.
This is an adapter to take a 1.25 inch (31.7mm) telescope adapter to a 2 inch (51mm) bore for calibrating the mirrors on your reflector telescope.
I ended up wrapping the adapter I printed with 3 layers of Scotch clear tape since my telescope is pretty worn, your mileage may vary
Telescope_Adapter.stl | 1.3MB |