Actually dude, its a rubber      "Thats what I said - isobutylene/isoprene copolymer"      "Uh dude, that would be a rubber"      "Thats what I said!"      ...      "isobutylene/isoprene copolymer"      ......      "Thats what I said!"      .........      "isobutylene/isoprene copolymer"    ............