M9/M9A1 HalftrackM9 M9A1 Halftrack The M9 halftrack series was manufactured by International Harvester when production facilities for M2 halftracks were determined to be inadequate to meet the needs of the Army and for export. Most M5 series halftracks were exported to the UK and to the Soviet Union. After World War Two M9 halftracks were widely used by many nations for decades after the war. Israel and even Communist China used them.