Yemen 1982 Progress in Air Transport series  -  number 10 of 14 designs in the series -  single value Chromalin Proof   100f value, SG687, depicting Plane and Satellite - in superb condition - excellent aviation, flight, aircraft, planes, space, rockets, satellites, telecomms, proofs, print techniques, postal history. If you cannot see item/country you are searching for on my fixed item listing please visit my ebay shop where I list huge stocks covering a vast array of topics/thematics! Chromalin Proofs are preproduction colourway matching proofs prior to print press proofing using a laminated film/toner system, they may also be called Matchprints. It is normal that only one or two Chromalins are produced per item before progressing to print proof stage therefore these items are extremely rare such that I only have one of each design to offer for sale.