how long to trijicon night sights last
20 times. Last year I sent a 12 year old ACOG back to Trijicon for replacing the vial one year ago. The price quoted at the time was 175.00 to replace the vial. Half life of the gas, depending on color, is about 12 years. Keep in mind, at the time I read somewhere there was a 15 year hiatus for tritium production.