This kit produces sweeping light bars that magically speed up or down depending on the ambient light level. In darkness, the bars (made up of 4 bright clear lens LEDs each) rotate very slowly, then as the ambient light increases the sweeping increases and takes on a radar screen appearance. If the ambient light is very bright the sweeping speed is so rapid that the kit appears to shimmer. This kit produces these effects automatically and makes a great attention getting display. Size of board: 2.6" x 4.1". Operates from one 9V battery (not included). Complete with all parts, PC board and instructions. Skill level 2. C6439R