U.S. Navy Type 4 Comfo Respirator
The U.S. Navy Type 4 Comfo Respirator featured dual disc filters and a flutter valve. MSA All-Dust filters were inserted inside the filter housing. The approved assembly consisted of: BM-2101 facepiece and BM-2133 filter. This example was made by Mine Safety Appliances in the 1940s. Here it has been paired with MSA goggles (made in 1944), however it is not known whether these two items would have actually been used together.