Comparing with a simple blue laser pointer only used for temporary dot positioning works, the real use of 445nm blue dot laser alignment just makes sure of continuous blue laser beam and blue reference dot projection from laser beam aperture. It is projecting moderate brightness blue laser light directly from a 445nm blue laser diode. However, comparing with 473nm blue DPSS laser system, this direct diode emission made blue laser diode module always makes sure of even more stable and reliable blue reference dot projection in long lasting use. Every time it gets advanced use of a metal heat sink cooling system, after getting even better thermal emitting than formal air or water cooling system, it just assures highly stable dot generation within long lasting work time of 8 to 10 hours per day.