I've actually got two, and one is used for the MRV and one is used for the M1. They hold the lights securely although it can be a chore to get the MRV back in the thing one-handed. You can't see it in the pictures, but there is an elastic loop of material inside the velcro outside which does a good job of holding things securely but makes it annoying to put them in sometimes. The belt-clip is fit for standard-sized belts, NOT really wide ones, NOT tactical ones - your normal everyday belt will do just fine. The clip can actually stay on your belt and the other part of the holster will detach when subjected to unreasonable force or when you press a release-button. My only complaint is that the things tend to spin - they don't stay facing up and down. There is a mini-carabiner on there which I generally try to hook to a belt-loop, but besides putting the thing right next to my Leatherman pouch, which IS stationary, I haven't figured out a way to make sure the lights don't twist around. Quality of construction seems to be good. Overall, it's a pretty good design with some major practical flaws.