Additional Details ------------------------------ Product description: Main Functions and Features: Screw back / Bezel with tachymeter / 24 hour hand / 1 type anti-magnetic clock / Calendar (date function) / Stop watch function (1/5 second measurement, 60 minute meter) / Charging amount display function / Small second hand included / Overcharge prevention function / Accuracy: Average monthly difference ± 15 seconds / Operating time: Approximately 6 months on full charge.