Lot 20527 – 1970 Calcutta Port Commissions 20np colour trials

1970 Calcutta Port Commissions 20np colour trials in four different colours (one in the chosen colour), with a single and a block of four of each, affixed on a cardboard page inscribed “Forwarded for selection of colours” and signed by the General Manager of the India Security Press, label affixed on the reverse indicating the colours used, very fine