Warranty: 5 YearsAnti-Magnetic: The movement is unaffected by exposure to strong magnetic fields, even those greater than 1.5 tesla (15,000 gauss).Chronometer: Label given to a watch which has undergone precision tests and received a certificate from an official body (COSC).Date: The day of the month, displayed in a window on a watch dial at the 3 or 6 o’clock position, or within a subdial at 9 o'clock.Helium Escape Valve: Decompression system which allows helium to escape from inside the watch when the watch is worn for professional use in pressure chambers. (Long-term underwater work, crude oil exploration, etc.)Master Chronometer Certified: Guaranteeing the Swiss industry’s highest standard of precision, performance and magnetic-resistance, as set by the Swiss Federal Institute of Metrology (METAS).Screw-In Crown: Self-locking crown, screwed into the tube of the case, used for highly water resistant divers' watches.Time Zone Function: Allows the hour hand to be easily adjusted to different time zones without stopping the watch.Transparent Caseback: A transparent caseback - frequently made of sapphire - makes it possible to see the movement inside the watch.Chronograph: The chronograph function is a mechanism for measuring time intervals. A chronograph watch can therefore be used to time events while displaying the time like any traditional watch.Small Seconds: A hand on a sub-dial which tracks seconds typically it completes a full rotation in one minute.Tachymeter: A tachymeter watch has a function for measuring speed. It is a chronograph with a graduated dial on which speed can be read in kilometres per hour based on a 1000 metre distance.Unidirectional Rotating Bezel: A bezel which turns in only one direction. Particularly useful for divers who cannot accidentally rotate it in the wrong direction, which could cause them to miscalculate their dive times. A rotating bezel makes it easy to measure elapsed time.Bi-Directional Rotating Bezel: A bezel which can be turned clockwise or anti-clockwise. Rotating bezels can be used to time events, measure elapsed times, or read second or third time zones.Diamonds: The hardest, most luminous precious stone whose value is calculated according to the 4C criteria: Cut - Carat - Clarity - Color.Numbered Edition: A watch series each of whose pieces is numbered sequentially in the order it is produced.Moonphase: A moonphase watch uses a function which tracks the phases of the moon. One lunar cycle is 29 days, 12 hours, 44 minutes and 2.8 seconds and includes four phases: new moon, first quarter, full moon, last quarter.Pulsometer: Pulsometer A watch with a scale to measure the number of heartbeats per minute.Telemeter: This precision tool can measure exactly how far you are from something that is visible and audible, such as your distance from a lightening storm.