This kit produces upward and downward wail of a "police siren" as push-button is depressed then released. Good for sound effects, parties, etc. Kit is small in size but produces a loud tone from a small speaker. Kit features transistor and IC circuitry which operates from 9V battery (not included). Size of PC board: 2 3/4" x 2". Complete with all parts, PC board and instructions. Skill Level 1. This kit requires soldering of components to the PC board while building.