A 20th Century Swiss thirty minute recording split seconds chronograph with unusual dial layout in a silver open face case. Gilt three quarter plate keyless movement with going barrel. Plain cock with polished steel regulator, uncut bimetallic balance with overcoil hairspring. Club foot lever escapement. Unusual white enamel dial with split centre seconds flyback chronograph and three subsidiaries for time, continuous seconds and 30 minute record, blue steel hands. Plain silver open face case with gold hinges, thumb piece, split seconds button in the band and gilt winding button for the chronograph. Plain silver cuvette, maker's mark “LW” in a rectangle.