Cuboid Glass X 1. ✔ Survival gear & compasses. 1.5×3×9mm (Brighter, great for tactical gear). 1.5×3×6mm (Ideal for small tools/keychains). Thesetritium vials utilize radioactive tritium gas (safe & non-toxic) to produce abright, self-sustaining light for over10 years —no batteries or charging needed!
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