This is a face shield I created that uses 3 hooks instead of 4, and the measurements match a standard 3-hole punch exactly, increasing ease of use and efficiency, as well as lowering costs dramatically. Standard 4-hole face shields are not in regular supply right now, so this uses standard A4 clear binder covers, which can be found in office supply stores or Amazon for $14 per 100 sheets. Simply use a 3-hole punch (small hole not large hole, the large holes won't stay anchored very well) and you are good to go. Cost is less than or roughly equal to $1 per face shield. already cleared and in use at the VA Sierra Nevada Health Care System. My print suggestions are: no rafts or supports, 100% infill, .8mm nozzle, .3mm layer height, 70mm/sec print speed, 2 parameters. On one Creality CR-10S5 (500X500) I'm producing 6 every 5 hours. I'm using a mirror for the bed and using the bed heat at 60. If you don't have a heated bed, I suggest using a .6mm nozzle, .2mm layer height, 100%infill, 100mm/sec print speed, 4 parameters and using masking tape on the bed (relevel your bed).