Sinn watch 757 bracelet the 757 model is a new addition to the sinn instrument chronographs collection the rotating bezel is attached using sinn watches special technology and a luminous triangle marks the 60 minute mark the 757 watch is equipped with valjoux 7750 automatic movement it performs 28 800 vibrations per hour and has 25 bearing jewels additional features include sinns dehumidifying technology extreme magnetic field protection pressure resistance and scratch resistant sapphire