Much more than just a writing instrument, the multiple lengths of fiber optic strands in this pen create a swirling panorama of light in motion for a unique, fun effect. A bright LED shoots up to the tip of each strand; as you move it around, the tips form light streaks that look almost like brush strokes. The wand and pen totals about 14" long. Long lasting batteries are pre-installed and not replaceable. Pens come in assorted colors with matching LED color (sorry, no individual choice of color).