The ДП-1 (DP-1) filter was a filter designed for use in areas containing Carbon Monoxide (CO). It functions not by filtering in the traditional sense, but rather by catalyzing the reaction of
Hopcalite Catalyst
Hopcalite - Wikipedia
Filter Hopcalite DP-1 pre plynovú masku Rusko ДП-1 - ARMYSURPLUS
Breathing Air Filters - Hopcalite (H2) 1 1/4", 300 / 178 - Ultramax Systems
Compatible reference E013HC
Midland Diving Breathing Air Filter 036120, X894151
Jordair Taste, Odor, & CO Air Filter FC-1006-TS, X58430
Deactivation and regeneration of hopcalite catalyst for carbon monoxide oxidation: a review - ScienceDirect
Filter element f/Hopcalite K013HC [4081680] | JA Compressor Parts
Hopcalite nanoparticle catalysts with high water vapour stability for catalytic oxidation of carbon monoxide - ScienceDirect
Ambient temperature complete oxidation of carbon monoxide using hopcalite catalysts for fire escape mask applications | SpringerLink