These encapsulated laser diodes are Class IIIa 5mW, with a 650nm red wavelength. They can be driven from 2.8V to 5.2V so they're great for your embedded electronics project.
This particular module has a lens attached that will turn the dot into a cross. This makes it particularly good for laser-vision guidance, targeting, and more! Simply connect power to the red and black wires and you will be lasing in no time.
The cross has a beam spread of approximately 60° in both directions. So from a distance of 5cm, the cross is 5cm tall and 5cm wide. The cross ends have a sharp cutoff so the shape is very clearly defined.
Please note: this is not a laser pointer. It's a diode with integrated driver. You still need a 3 to 5VDC power supply. These diodes are 5mW output, and have a safety label marked on them.
Adafruit Product Page: https://www.adafruit.com/products/1058