Description:
Tritium illumination is the use of gaseous tritium to create visible light. As tritium illumination requires no electrical energy， it is widely used in applications such as emergency exit signs and illumination of wristwatches， necklaces and key chains

Main Features:
Filled with self-powered gaseous tritium
Glows continuously for 15 years
Unique gift for friends and couples
Green， yellow， blue， orange and red are available