Many of the Vostok-Europe models feature Tritium tubes (trigalights). These highly specialised light sources are manufactured by Mb-microtec of Switzerland and provide excellent illumination with no external power source and never need to be recharged by the sun or otherwise.
Trigalights are tiny glass tubes that are laser sealed, internally coated with phosphorescence and filled with a minute amount of tritium gas. The permanent light occurs when the electrons emitted from the gas excite the phosphor. They do not require any external power source or require recharging and will glow continuously with a life span of more than 10 years. Click for more information.