HiLetgo 10pcs 5V 650nm 5mW Red Dot Laser Head Red Laser Diode Laser Tube with Leads Head Outer Diameter 6mm

Quality laser diodes. Operates directly from 5 volts... coolly,Expected lower quality, due to the low price, butwas impressed with the quality of the product, andwas further impressed that there was more than oneat this price level.

Bought this to make an automatic laser pointer for my cats. My initial fear of the lights being dim were immediately received when I hooked it up to the Arduino. Great performance. Quality so far seems pretty good, however it seems like the wires are lightly soldered on. So far none of them have broken free. Very tiny, which is great, and probably the best value for the money considering quality and quantity. Love them!

I use these in models, and they are great for that use. One or two out of the lot don’t work properly but that’s okay at this price point. Make sure to test before you solder. The lens is adjustable and you can rotate till you have a nice sharp point of light. These have been great.

The media could not be loaded. These diodes at 50 cents a piece are one heck of a bargain. To dispel some of the myths and reviews here is useful information.They only require a 5-volt power supply, that's it. I used an old desktop Christmas tree power/controller to power the diode, it Powers the diode quite nicely at 4.5 volts, and using the controller I get different beam options, (video attached) remember no driver boards or power modules needed, use batteries, 5 volt power supplies, (the diode will work at 3-5 volts although at 3v it's not that bright)THEY ARE FOCUSABLE ! I have seen complaints that they are out of focus, that's because the barrel of the diode is threaded, you can screw the forward portion of the diode barrel in and out to focus it at different distances, it is not one solid piece of brass but split in the middle.This is my second purchase of these, all have worked flawlessly and consistently.One caveat, the wiring is thin, as others have stated, they will break off at the solder joint quite easily. My suggestion cut down some electrical tape and wrap it around the board and wires to act as a strain relief, or, encapsulate the the board and wires with hot glue, this is the best way.Although not tested, my 40 years experience in lasers tells me these are hotter than a typical 5 MW laser diode.

These LASERS work perfect, are really bright and the cost is outstanding. Super Deal...

These work, but they are not aligned at all, which means you shouldn't expect a 'straight' beam out of the cylindrical housing. They all shoot off to one side or another. If you don't care about accuracy, then these are cheap and work great. Unfortunately though, I have yet to find inexpensive laser diodes that actually project the beam in a straight line with the housing.

All units work. Ran directly off a 4.5V battery pack. Bright, but has marginal particle flare (expected from low cost optics). Beam spread is about 5/8 inches at 25 feet. I've read this can be adjusted, but the brass/copper head is so tight to the body that I fear I'll damage the unit trying to adjust it. Leads are little short - about 3 inches long, but overall I'm pleased with these units.

This laser diode is perfect for my application which is a laser sight for a Bug-A-Salt unit. However, it pulls 50% more current than the published specifications. The one I tested pulls about 29 mA at 5V instead of 20. I plan to run it from 3 AA batteries in series so I expect it to pull about 25 mA which is fine. The dot size is pretty large but I don't expect miracles for the price, so I'm pretty happy with this product.