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Verified Purchase(What is this?)
I too had the intermittent loss of power, not sure if its the battery end cap (slight rattle) or the way AAA's +/- nodule doesn't cup (so it slips when spring doesn't force them together). I took a small piece of aluminium foil and folded it over couple of times to get a tiny disc, placed between the battery the connection is improved and I've no longer had any issues.
As other reviewers have noted, this is probably rated based on visible radiation - the dull violet. Anything that steps down the ultra violet to visible results in very bright reflected light. The complaints about the beam not being visible are probably due to not understanding why the dot is visible. The beam is ultra violet and can't be seen, it strikes an object and the power is stepped down into visible light, this is then reflected back to your eyes as the purple dot. Essentially the same is happening when the beam strikes a fluorescent surface, but more efficiently. The beam can be observed by shinning the laser through a glass of water (careful of reflections). The dot appears to be 'fuzzy' and undefined compared to a red laser, because your observing returning light that's been partially scattered. UV light is actually far 'sharper' than red light, currently in R&D/commercialisation to replace blue ray with a massive jump in data storage for the same size media.