Small card box containing a roll of Radar blocking 'Window' or 'Chaff'. Contains of a roll of thin aluminium strip or aluminized paper strip with a length of cotton tape attached to one end. These were thrown out of bomber aircraft in order to jam German Radar signals and prevent them from plotting the positions of approaching allied aircraft. Approximately 8 x 8 x 1.5cm. Excellent unused condition. Three rolls available, individually priced. Stock code M20443.