I purchased a MC3 Trust Fire last year and it only last a couple of months before failing. Giving them another try, I purchased a MC5 Trust Fire because I wanted more lumens. I charged it overnight night and upon trying it out, it went from the brightest mode to dim almost immediately. I put the light back on the charger again, tested it on a voltage meter and again it went to dim immediately. I reached out to Trust Fire - worst customer service period! They had me take a photo of the battery to make sure I had the correct battery. Several days later they responded with requesting video to prove it went to dim. I sent them that video footage. They now requested more video proof to show the battery being tested, and then to confirm I slid in the correct battery, and then turned on the flashlight all in one continuous clip. I did that. This is now going on over 2 weeks of emailing back and forth, I have not heard back from Trust Fire and now I'm out over $120 and 2 flashlights. Unless this gets resolved soon and properly, I would not recommend putting your trust in Trust Fire. If there is a resolution, I will post an update. But as it is looking, I wouldn't count on it. I'm in the hole and in the dark in more ways than one. Very disappointed in customer support and service!!!