This is my first custom print. You attach this to the end of a refractor telescope to allow for bright stars to have what are called Diffraction Spikes. Some like the aesthetics of diffraction spikes (caused by the secondary mirror support) in astroimages.

The original design is for a 70mm Stellarvue telescope, but should be able to be scaled to your telescope size.

The astroimage is of NGC7789 using this print. As you can see there are diffraction spikes around brighter stars.