1931-37 C of A Watermark 6d Carmine and Yellow-green strip of 4 used with 1d of the same series tied by Abbortsford cds on 1936 (27 Oct) unsealed cover from Melbourne franked 1d, 'T' in oval with mss '2d', the 2/1d postage collected representing the total due from multiple items to the same addressee. Very few covers bearing the 6d are recorded (BW cat AU$2000), the strip of 4 being the largest recorded multiple on cover. A very fine and highly desirable franking, and one of the most important postage due covers