The Vickers 6-ton tank or Vickers Mark E, also known as the "Six-tonner", was a British light tank designed in 1928 in a private project at Vickers. Though not adopted by the British Army, it was picked up by several other armed forces, and licensed by the Soviet Union as the T-26. It was also the direct predecessor of the Polish 7TP tank.

The 10th Cavalry Brigade was a Polish military unit in World War II. It was the only fully operational Polish motorized infantry unit during the Invasion of Poland, as Warsaw Armoured Motorized Brigade was not completed by September 1, 1939.