Why plague doctors wore those strange beaked masks

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Plague Doctor Mask, Steampunk Beak Mask Cloak, Custom Medieval Mask Hat, Halloween Cosplay Mask Costume, Gothic Mask, Viking Piracy Hat - Etsy

Steampunk Plague Doctor Mask Cloak, Personalized Medieval Mask Hat, Punk Gothic Mask Costume, Halloween Party Cosplay Mask, Black Beak Mask - Etsy

How to Make a (Steampunk) Plague Doctor Mask — Lost Wax

HAOSUN Plague Doctor Mask and Cloak Halloween Costumes for Men 3 in 1 Scary Masks for Adult