I've seen a handfull of these Longines with various dials of which one is in the Longines Museum collection and pictured in the latest Goldberger book on page 576/7. This sofar is the only one I've seen with this silver blue index dial... It's a 40mm Longines Admiral with 'Flying Soucer' case and absolute stunning original dial. The watch is NOS, like new! It's even got it's original band with Longines buckle attached. It was manufactured in 1970 and is ref 8581. Movement is Longines Automatic Cal. 431 and working perfectly. The new condition with rare dial combined with the all round case makes this watch truly special.