if your talking about stuff like the kip-kay flashlight laser then go ahead and waste your money. you have to have a driver circuit for a laser diode. the amps in batteries arent regulated and a laser diode need regulated current. you must have the driver circuit or burn the diode out. a 20x dvd burner red diode(long open can) is capable of making a 660nm(red) >250mw of power. basically you can get a quarter watt laser from a 18-22x dvd burner that has the long open can diodes. short open cans can do <250mw. most closed can diodes cant push anymore than about 200mw.