Because built-in power LED lamp life of only 10,000 hours and 50,000 hours compared to the external power supply, the use of cost apparently five times higher. Moreover, in the course, whether it is damage to the LED, or power supply is damaged, usually two to be discarded. The external power LED lamp, which can be a bad throw which.

   External power supply, not only high efficiency, long life, but also can increase the manual or automatic dimming dimming and other special features, which are built-in unmatched!