Quarantine Coloring Book
The Czech Ochranná Maska M-10 was one of the many licensed copies of the U.S. ABC-M17 Field Protective Gas Mask. This example was made by Gumárny Zubrí in 1973.
Ochranná Maska = "Protective Mask"
Similar masks in my collection: U.S. Army ABC-M17, U.S. Army M17A2, Bulgarian PDE-1, Polish MP-4, Polish MP-4M