Fiber Optic Light Kits produce wonderful lighting effects for a wide variety of craft and hobby applications. Almost invisible translucent fibers emit light from their tips only. The flexible fibers can be held in place, if desired, with glue, tape, wire, etc. Fiber Optic Light Kits include either 12" or 24" long strands of 50 fibers each. Uses 2 AA size alkaline batteries (not included). Battery case has on/off switch. Case measures 2-1/4"h x 1-1/4"w. Fiber optics holder is 2-1/8"h x 3/4" diameter.