I have a lux meter. I bought it and thought it was the wrong application. Does not measure the entire spectrum, and cannot submerse it. I was of the impression that it is for agriculture. Not going to grow pot lol. Which is what all the you tube videos are about. It is a Milwaukee. Will look again but did not find much useful info on this siteYou can approximate PAR pretty well with a simple LUX meter. There's a bunch of info on here about it.