Aliens are coming in their warships and are dropping their bombs on you! The only way to defend yourself is by neutralizing their bombs before they reach the ground. The bombs fall at different speeds and in different directions. This kit includes 19 LEDs of three different colors (red, yellow and green), 3 action switches, a circuit board, three ICs, and other components. Operates from 9V battery (not included). Size of board: 4 1/2" x 3 3/4". Complete with all parts, PC board and instructions. Skill Level 3.