Need help with new laser

[destroyer70813]

I had recently bought a laser and it wont turn on. I checked the battery and it works just fine, so theres something wrong with the laser but ibdknt know what

 

[Species8472]

Some lasers require the positive/negative end of the battery to be inserted a certain direction. Some lasers have a protection circuit that stops the laser from getting fried if the battery is inserted the wrong direction. Make sure there isn’t a cap blocking the lens. What brand and model of laser and battery do you have? Someone with more expertise will probably chime in.

 

[hakzaw1]

"most.'' greens (made with an IR laser diode then a lens that makes it green are almost always neg to the front- the makers must tell you and then you need to mark that inside the tailcap with a fine point sharpie.. BIG risk trying to find that out with trial and error IMHO.