Pen shape laser pointers are an excellent light source for ray optics and useful tools in presentation. These new, inexpensive and safe class III diode laser pointers can be used in physics labs to study reflection, refraction, and other light properties. The red, green and blue lasers offer different wavelengths for interference and diffraction experiments. The use of different color lasers will make any classroom presentation more effective and interesting. The red laser projects a light beam at a wavelength of 650nm, the green laser emits a light at 532nm, and the blue laser features a wavelength of 405nm. These lasers operate on two AAA batteries, draw a current of less than 60mA, and produce 5mW of power. Dimensions: D=13mm, L=165mm. At this time we only have red laser pointers available. The one on the right in the image.