Harmonicas were scarce in the United States during World War II. Wood and metal materials for harmonicas were in short supply because of military demand. Furthermore, the primary harmonica manufacturers were based in Germany and Japan, the enemies of the United States and the Allied forces in the war. During this time, Finn Haakon Magnus, a Danish-American factory worker and entrepreneur, developed and perfected the molded plastic harmonica. The plastic harmonica used molded plastic combs and far fewer pieces than traditional metal or wood harmonicas, which made the harmonica more economical to mass-produce and more sanitary. Though the plastic reeds in these harmonicas produced a less distinctive (and, to many ears, inferior) sound than their metallic counterparts, Magnus harmonicas and several imitators soon became commonplace, particularly among children. The patent for the plastic comb was awarded to William Kratt of Wm. Kratt Company in 1952. During World War II, the War Department allotted a rationed supply of brass to Kratt's factory so they could continue to produce harmonicas that the Red Cross distributed to American troops overseas to boost morale.
Harmonicas were scarce in the United States during World War II Wood and metal materials for harmonicas were in short supply because of military demand. Furthermore, the primary harmonica manufacturers were based in Germany and Japan, the enemies of the United States and the Allied forces in the war. During this time, Finn Haakon Magnus, a Danish-American factory worker and entrepreneur, developed and perfected the molded plastic harmonica. The plastic harmonica used molded plastic combs and far fewer pieces than traditional metal or wood harmonicas, which made the harmonica more economical to mass-produce and more sanitary. Though the plastic reeds in these harmonicas produced a less distinctive (and, to many ears, inferior) sound than their metallic counterparts, Magnus harmonicas and several imitators soon became commonplace, particularly among children. The patent for the plastic comb was awarded to William Kratt of Wm. Kratt Company in 1952. During World War II, the War Department allotted a rationed supply of brass to Kratt's factory so they could continue to produce harmonicas that the Red Cross distributed to American troops overseas to boost morale.