Certina DS-2 green manual wind watch

Rare Certina DS-2 with green dial. Crystal is in good condition, no major scratches or cracks. Dial is clean for its age and its colors have remained bright. Case has signs of age and use and the crown is original. Steel mesh bracelet has been used. Service history is unknown, but the watch works well. Date changes and the watch is running approximately +- 20 seconds per day.