Same as Polychorus. Kurt had two of them apparently, and used them on the Unplugged show. However, I don't know what songs he used it on. I don't think he used it one any songs, but Guitar World says that he was arguing with MTV techs over the various qualities of the Echoflangers.
THE FORGOTTEN MARINES OF TARAWA. During late-November 1943 one of the most savage battles in the history of the Marine Corps took place on the tiny island of Betio, located in Tarawa Atoll. The capture of this island took three days and cost the lives of 990 Marines and Navy Corpsmen. In addition to these, another 2,200 were wounded.
In August and September 1943, the 28th Marines and parts of the 13th Marines arrived from the States. By mid-October the last units of the 5th left for Hawaii to bring the whole division together once again. The 28th Marines brought with them to Camp Tarawa their lion mascot named Roscoe.