What watch store? iirc Luminox guarantees their trit tube watches to stay the same brightness for 10 years then slowly dissipate after-wards... going on to say (this is what they used to claim they were recently bought out) they would last up to 20+ years. This might have changed in the last 2 years, but this is what they used to claim. I was into Luminox in the mid 90's when people knew very little about them. They had a very poor marketing team/plan and customer support was zero nil nada back then.