Optrel Clearmaxx Tear-off Foil Protector - 5000.039

These protectors looked like they would adhere completely to the clear mask and not impede visibility (like a phone screen protector), but they actually only adhere at a couple points on the sides and inevitably have a slight air gap between the foil and the mask itself. As you'd expect, this makes it noticeably less easy to see through the mask and I would pretty much call them unusable unless you are just doing a very dirty task for a very short time. I would definitely not want one of these on my mask at all times.