It’s called an Equivisor. They are AMAZING and $40 AUD each. I sew the nose flaps on (from Caribu @ $6 ea). This year I tried a new technique of using teeny cable ties to attach the noseflap in the corners. Over the nose I used super strength velcro glued on with Tarzan Grip on the upperside of the mask, and a piece of sheepskin on the underside (this mare needs sheepskin). That way I can remove the nose flaps in winter, or to wash them, as they don’t last as long as the masks do.
This mare is 25yo and has nasal tumors and it’s a fine balance between keeping her safe from the sun (she burns like bread in a toaster) and overloading her skin with things that rub.