Fortis Easy Math Slide Rule Compass Watch

Offered is this Fortis Easy-Math Watch that winds, sets, and runs great. It keeps excellent time. The crown at 2 operates the internal rotating bezel and second crystal below the watch crystal that is seated into the rotating bezel so that the compass points and minute timer may be rotated as well. The outer portion of the internal bezel functions as a slide rule (as in the Breitling Navitimer). The gray portion of the rotating crystal can be used as a minute timer by lining up zero with the minute hand to count time up to 60 minutes.  The compass portion of the crystal rotates to help determine direction. If you place the watch horizontally and point the hour hand at the sun, the point half way between the minute hand and 12 is due south. One can then line up the south pointer on the internal rotating crystal at this point, and use it to determine other directions. BRAND:  Fortis GENDER:  Mens CASE:  Chrome Plated Bezel, Steel Back CASE BACK:  Screw-down, marked Easy-Math, Brev. + Etr