The Panther was a tank fielded by Germany in World War II that served from mid-1943 to the end of the European war in 1945. It was intended as a counter to the T-34, and to replace the Panzer III and IV, though it served along with them as well as the heavier Tiger tanks until the end of the war. The Panther's excellent combination of firepower, mobility, and protection served as a benchmark for other nations' late war and immediate post-war tank designs and it is frequently regarded (along with the Soviet T-34 and American M4 Sherman) as one of the best tank designs of World War II.
Until 1944, it was designated as the Panzerkampfwagen V Panther and had the ordnance inventory designation of Sd.Kfz. 171. On 27, February 1944, Hitler ordered that the Roman numeral V be deleted from the designation.Design work on the Panther II began in February 1943. The main aim was to secure maximum interchangeability of parts with the Tiger II heavy tank in order to ease manufacturing. The Panther II had a hull similar to the Tiger II, and also shared nearly-identical steel tired road wheels (seven versus the Tiger II's nine), "contact shoe" and "connector link" track, suspension and brakes.                                                                                                                                          -- Wikipedia