Prusa RC3 Elastic substitute
thingiverse
If you're having trouble finding the buttonhole elastic for the RC3 face shields, you might want to consider using an elastic adaptor like https://www.thingiverse.com/thing:4310197 or printing the entire thing in PETG instead. I don't think PLA would work well due to its stiffness, but PETG could be a viable option. While it's not ideal since it won't adjust to fit different sizes, you can easily create various sizes of it. The best part is that it's disinfectable and latex-free.
With this file you will be able to print Prusa RC3 Elastic substitute with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Prusa RC3 Elastic substitute.