It is said that the origin goes back to the year 1364 in Paris. When the then French king, Charles V, saw the numeral IV on the clock on the tower in his palace, he disliked the way to express 4 by the roman numeral IV, because it seemed to him like V minus I (5 minus 1). He immediately ordered to change the “IV” to “IIII”. Since then using “IIII” on the dial/face has become the standard among watch makers.

The luminous paint currently used for our watches produced and sold does not contain any radioactive substance. Light storing pigments are used instead.However, promethium 147 (half period: about 2.6 years) was used for luminous paint of some products before 1998, complying with laws which set its safety standard at that time.

Be sure to remove the protective sticker on the case back before use.Otherwise, sweat or moisture may creep in between the sticker and the case, causing stains or corrosion to the case, which may lead to a rash on your skin.

Diver's 200M (Air diver's 200m) watches are specifically qualified for diving, while WR200 (Water resistant 20 bar) watches are designed for the people who touch waters very often in their daily lives. So, Diver's 200M (Air diver's 200m) watches go through severer water resistant tests before shipment than WR200 (Water resistant 20 bar) watches do.

A leap second is inserted in order to adjust the time difference between UTC (Coordinated Universal Time, the international time standard), which is defined by atomic clocks using the frequency of the Cesium atom, and UT1 (UT: Universal Time), which is derived from the Earth's actual rotation. The International Earth Rotation Service (IERS) makes the decision of when to insert a leap second in UTC. Because the Earth's rotational time varies, a leap second is not applied regularly. When applied, the first priority of insertion is given to the end of December and June, and the second priority to those at the end of March and September.After insertion of a leap second, the time on your watch gets one-second faster than before.Be sure to adjust the time on the watch.Signals which radio controlled watches use contain updated leap second information and the watches adjust the time automatically as they receive signals after leap-second insertion.

It is a function equipped within Eco-Drive watches to reduce power consumption.The hands stop automatically when the solar cell of a Eco-Drive watch does not generate power for a certain period.The watch is still working internally to keep the time and calendar even while the power save function stops the hands. The power save status ends automatically and the hands return to indicate the current time when the