3590.50.00. $800 off eBay in 2007. NASA stuff came to me from Omega HQ Call Center Europe when I asked if they had any promotional material they wanted to get rid of in the literature center. The woman I spoke with back then was extremely accommodating. Hesalite is virtually blemish free, extremely careful with the watch when I wear it. Original bracelet was removed when new and never put back on the watch. Some dust, reflections, and arm hair on the bezel, but it is blemish free.