Giving this one some wrist time today. Need to keep it in trim until the regatta season kicks in again!
😉
Elvström Lemania cal 1345.
The special bezel with the compass markers, together with the "First Mark" and "Reach" indicators are used to calculate tack angles for an international/Olympic regatta racetrack (
http://en.wikipedia.org/wiki/Olympic_triangle).
The "Elvström" name comes from the man who invented this function in a watch, he is also a famous yacht designer and four times Olympic and eleven (11!) times World Champion. (
http://en.wikipedia.org/wiki/Paul_Elvstrom).