Figure 10. The stronger; nationally distinctive goggles, which tended to be used in the last couple of years of WWI. Although pilots still had the freedom to wear whatever they felt comfortable with, these tended to dominated certain air forces. a) the RFC/RAF Mk I & Mk II goggle mask. b) the French Meyrowitz goggles. c) German ‘Standard Goggles’, developed from a French design. d) U.S. Resistal NAK goggles. The U.S. also used the RAF and Meyrowitz goggles in large numbers whilst their manufactures tooled up.