The Casio B640 has a light-emitting diode (LED) wich is used to illuminate the watch face. This model is equipped with a multifunctional alarm. One of these alarms is a snooze alarm. This clock has the perfect alarm for your type of appointment. The model is equipped with a total of four repeat alarms 1. Daily alarm, sounds at the same time each day, 2. Date alarm, e.g. to help you remember birthdays, 3. Monthly alarm, sounds on the same day at the same time each month, 4. Alarm for every day of a particular month. You can wear this watch when wu take a shower or take a bath - it is tested for water resistance up to 5 bar / 50 metres. The metres value does not relate to a diving depth but to the air pressure used in the course of the water resistance test.