1981 RAF Mountaineering Expedition to Masherbrum Signed Cover

28th May 1981 Special Wiggins Teape Tyvek 10 Lightweight Cover Commemorating the RAF Mountaineering ASSN Expedition to Masherbrum (25,600ft) in the Himalayas. One of the Worlds highest unclimbed mountain peaks at the time. The cover is signed by 7 members of the expedition on the back & comes with a presentation folder.

Superb condition, unsealed, with information insert card & Folder.

It mentions on the cover that 3000 of these Lightweight covers accompanied the RAF members on the Expedition, but this is the only cover I have come accross!