Lensatic Compasses seem to be priced from $5 to $100 USD. What features should I look for when buying one?
Lensatic Compasses are often used by the military, because the are:
The things that I would look for in a lensatic compass are:
The radioactive tritium particles are low energy beta particles and are not harful for external use, (they cannot pass through clothing or skin). As long as you don't swallow them you are fine.
The reason for the illumination is so that the compasses can be used without any external light source. The military, especially special forces, love this. It allows for "dark" navigation.
All radioactive isotopes have a half life. And Tritium's is 12 years, so in 12 years your compass will be half as bright as it is the day you bought it, then 12 years later, another half life. And so on.
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