My friends I give you the mickey mouse gas mask for American children during WW2 by u/SacredBoom96 in WTF We found other unrelated posts on Reddit that contained the claim.

Sometimes parents have to explain things to their kids in more child-friendly terms. During World War II, that meant outfitting a child with a weird Mickey Mouse gas mask. It was 1942, just about ...

During World War II, the American military began investigating methods to protect the civilian population from domestic saboteurs. One solution the military devised was this extremely eerie Mickey ...

The Mickey Mouse gas mask designed by Walt Disney to protect American children from chemical warfare Walt Disney helped to design children's gas masks that looked like Mickey Mouse during World War II ...

WW2 Clips. A teacher tells her young pupils how to put on their gas masks correctly. BBC School Radio. BBC Teach.