Less than 1" x .5" x .5" (2.54 cm x 1.27 cm x 1.27 cm), LED markers that attach to standard 9 volt batteries, for use on the stage, or other low-light level situations. They give off a small but very visible light (red, yellow or green) that help performers to find their marks, or to see the edges of platforms or equipment in the dark.
Snap-it beacons are much easier to see than glow-tape, so dancers can easily find their marks. Lay the beacon on its side with the lighted end facing upstage, the battery then blocks all the light from the audience's view. The point of light provided by the beacon can easily be seen by the dancers or performers, even with stage lighting in their eyes.