Laser Diode Module 650nm 5mw Red Laser Diodes 2Pack (Cross)

Purchased for and project, and work well. Good quality and price

got two line lasers as ordered. 3-piece housing is solid. front pieces was lose but that is necessary to adjust it, to get sharp and bright line. with lense unscrewed about 1.5mm it got really sharp and consequently brighter. if it is not focused, it will be dim since the light spreads too much. product is described as using 3V power... it start emitting at 2.2V and draws 19mA, at 3V still draws 19mA. at 3.7V draws 15mA, at 5V it draws 15mA and it does not get warm. i pushed it to 10V and saw no issues (works, does not get hot), did not try to go beyond that 3-9V range allows for plenty of supply options.

Found the single line versions to be very bright, when testing at 3.3V supplied from an MB102 breadboard module. I attached Dupont connectors to the thin wires, which were plugged into the breadboard. The laser line output angle is close to 120 degrees. I could collimate the beam with the focus ring to produce a line width of ~4 mm at 5.5 meters, against a white wall. The line was still clearly visible in daylight, in a room without direct sunlight and two small windows. Of course, at shorter distances the lines were finer and much brighter. I was able to power both lasers in a parallel configuration from the MB102. I could see both lines at 5.5 meters. The 5.5 m distance is not necessarily the maximum to see the lines. The limit was the room size. In a very bright room with sunlight, at 5.5 m, it would be marginable to see the beam lines.

These are really nicely built. They arent dinky laser modules like those in a cheap laser pointer... they are quite heavy! The only drawback it that they are only 5mw so are quite dim (why 4 not 5 stars).

The ends have a little distortion, but only about 3/4 inch on each side when 12 inches wide. One thing to note, if you take the lens off, you will see that the laser is putting out a rectangle, not a spot, so not only do you need to focus the lens, but you will see that only in one orientation of the laser body will the line be the thinnest it can be. Since the lens rotates with the focus, the focus is only accurate to 1/2 of a turn of the focus ring. So to keep the focus as tight as possible when rotating the line, you need to turn the whole body, not just the focus ring.