Under normal circumstances, there are three colors of Cheap Laser Pointers pen, they are green, blue and red. Because of the different wavelengths, so showing the different colors. Certainly, different colored pens have different functions. Green laser pens are highly used in astronomy students as it has a different wavelength from all other lasers. It makes a beam rather than making a dot on the surface. This looks more appealing and people tend to buy this laser more. Another thing to remember is on how to use your device safely. We all know that the production of the product is controlled by the FDA especially when it comes to safety. As a user, we should know the dos and don'ts of using this device. First, we should avoid frequent dropping or shaking of the device. This may damage the insides of the device and may cause malfunction that can destroy the device or may have harmful effects such as explosion. Prevent the light of the 5mw 532nm green laser pointer pen on porous or easily flammable materials for it may cause large fires or even blasting. The light of the laser can cause severe damage to the eyes when aimed at it and may even cause permanent blindness. Follow the safety precautions and avoid the light from other people's eyes. The items that are described to emit between 5 mW to 500 mW output power are called the Class IIIb or IEC Class 3b. The ones that are classified under this category are not legally permitted to be advertised as buy green laser pointer cheap or demonstration laser products. The instruction guides of these must clearly state and describe its hazard classification and output characteristics. These are dangerous and illegal to use in pointing towards moving vehicles, airplanes, people, animals and other material prone to damage when exposed to extreme beam light. The FDA also has mandated a limit for the laser pointers' emitted power. The products that are allowed for pointing and demonstration are under the Class IIIa. So, if you want to buy a laser pointer pen, it is very important for you to know clearly about all the informations about the laser pointers for sale.