In the early days of watch making radio-active radium and then tritium where used by some manufacturers on dials and hands. This is now a thing of the past. We pride ourselves on the fact that we have never used any radio-active materials in our products. The luminous material used by us is Super-Luminova and, as it is not radio-active, needs activation by being exposed to bright light for an extended period of time. The luminosity thus achieved will last, although with a decreasing intensity, for up to 8 hours.