This listing is for one M140 M-Type (has the little dot above the square symbol) laser diode. The diode emits a 445nm wavelength with output power reaching 2+ watts. Each diode is carefully extracted from a laser diode array. Each diode is tested to ensure functionality.
 
You must know what you are doing before hooking these up. Reverse polarity, excessive current and high heat will damage or ruin these. A constant current laser diode driver is required to drive the diode, never connect directly to a battery. Recommended driving current is between 1A and 1.6A. The current should not exceed 1.8 amps!!! The diodes must be inserted in to a laser diode module w/ heat-sink before energizing to dissipate heat. A glass lens should be used as well. 
 
Always wear protective safety glasses or goggles that block this spectrum and intensity of light... You've only got one set of eyes!!!