[TrueBlue711]

So I never really looked deep into this before getting my Trijicon RMR, but how long does tritium really last before you need to send it in to get the tritium replaced? 5 years? 10 years? A lifetime? Would constantly having it in the sun/light affect it's lifespan? Would keeping it stored in the dark extend it's life? Just general knowledge about tritium would be appreciated. Thanks!