Promethium is a radioactive element, not too good for human health; and now the watch night material is tritium tritium, tritium is very safe.
Long-term use of watches, such as collectibles, need special attention, if the minute hand is always fixed in a position, then the pointer above the night on the dial there is injury. With the night to do the material, it is possible to change the color of the dial, mainly silver side of the dial, other types or colors probably will not change the location and the corresponding position of the pointer.
If you find the watch pointer shift or fall off, it must immediately stop the watch, no stop seconds device, it should also pull out the table, so that the watch gradually stopped, then do not go to the needle and the chord The You can put the watch glass down, and then sent to the watch shop in time to do maintenance.
In case the watch has been violent vibration, but also carefully observe the pointer, especially the hour and the dial of the distance between the changes in the blue steel pointer rust, it should be done in time to dress. Belong to the collection of watches, it is best every six months a year, re-dial the needle, the winding