The light is bright enough and the module appears to be nicely built. The body of it is impact resistant plastic and the head has a rubber coating. It even came with energizer batteries. There are 2 o-rings for keeping water out. The led has a good white color to it. It is bright and does not have the odd halo that some have. There is no button, it is a turn activated light. To change modes, turn off and on quickly till you get the mode you want. This is a good thing for switch life, but it also means there is no beam width adjustment and can not be turned on/off without two hands. That is a problem for me. It would be hard to use in emergencies. Personally, for the price, it is ok. I will probably get a different light for my hand and keep this one as a spare clipped on.