The L4 is a handy, unbelievably bright LED light that's powered by 3 AAAA alkaline cells (included). The light weight, slim profile design fits neatly in your pocket and comfortably in your hand. A tail button switch provides quick on/off or momentary activation. The clip is virtually unbreakable because it is molded to the Xenoy body as one unit. And because it is molded out of polycarbonate resin, it won't cause sparks and is safe to use in electrical environments.