And the back of old open face watches unscrew by turning right to get to the lever for time adjustments, don't pry .. can't tell you how many of them I seen with the case all screwed up from someone trying to pry them open ... closed face watchs there is a small bulge on the back for opening with your thumbnail but open face watches the back unscrews ... it is so sad to see a watch that survived over a hundred years with the case all destroyed from trying to pry when it should be unscrewed