These maps originated during WW2 for pilots who might be downed, and continued in use for navigation etc.  They were compact, lightweight, detailed, easy to read, and extremely durable.  They look and feel a lot like silk, and that's their colloquial name, but they were actually made from rayon.  This is an original; not a reproduction.  This particular one was printed in 1953.

This map shows the Stalingrad region on one side and the Stepnoy region below that on the other side, both very important to the battle there in WW2.  Size is 22" x 24".  Scale is 1:1,000,000 so 1" is approx 16 miles, and 1/16" (which you can discern) is 1 mile so even villages show up.  There's a tremendous amount of detail including not only towns, roads, rivers etc. but also elevation lines, all very clearly visible.  See the detail pictures.

Such silk maps were issued by the US and British Armies and Air Forces.  This one is from the British General Staff Geographical Service so most likely Royal Air Force.

Listed as "New" because it was never used and the bright colors and finish are very little changed from new.  In fact it has probably been unfolded only once, for these pictures.

All such maps are heavily creased because they were delivered and have been stored that way.  If desired eg. for framing, ironing should fix a lot of that.