BREITLING NAVITIMER COSMONAUTE REF. 81600B, SOLD IN 1990 Three body tonneau stainless steel case, n. 4952, revolving bidirectional slide-ruler bezel, faceted lugs, snap on back with relief logo and centigrade and fahrenheit scales engraved, round pushers and Breitling crown. Not original strap and buckle.
Black dial signed, 24-hour Arabic numerals indication, minute and 1/5th of second divisions, outer calculations scales, silvered subdials for the seconds, 30-min and 12-hour registers. Luminescent bâton hands.
Signed manual winding movement, rhodium-plated caliber LWC 1783 24, n. 4406496, 17 jewels, lever system for the chronograph, lever escapement, monometallic balance, flat hairspring, Incabloc shock-absorber.
Fitted with Breitling box, booklets and warranty. 
Diameter Ø: 40 mm
Note: working.