Marking the 10th anniversary of Botswana's Okavango Air Rescue organisation, this Big Crown ProPilot Big Date Limited Edition pairs a brushed-and-polished 41mm stainless steel case with a green dial whose texture echoes the grasses of the Okavango Delta. The commemorative screwed caseback is engraved with an O.A.R. aircraft flying over the delta's islands alongside the individual limited-edition number. Limited to 2,011 pieces — marking the year O.A.R. was founded — each watch arrives in a speci...