MADE IN THE USA! Tritium is more expensive but has a much longer luminosity life. Phosphorus is a good way to go too, you save a little bit of money. Either way, Cammenga makes a tough wrist compass that won't let you down!
The World's No 1 Military Compass
Built To The Demanding Specifications Of U.S. Fighting Forces
Battle Tested - Shock, Water, Sand Proof And Functional From -50ºf To +150ºf
Seven Tritium Micro Lights Allow For Navigation In Low-Light Conditions
Equipped With A Magnifying Lens, Sight Wire, And Dial Graduations In Both Degrees And Mils To Ensure Accurate Readings
Copper Induction Dampening System Slows The Rotation Of The Magnet Without The Use Of Liquids
Built To Last With An Aluminum Frame And Waterproof Housing