There are many types and sizes of compressors. One of the more common types is the mobile construction air compressor. These towable compressors are found at construction sites and are used to power pneumatic tools such as jackhammers, tampers, nail guns, and pumps. Operating these tools also requires some understanding and knowledge of how to operate the compressor that powers them. In this module, we will cover the principles of operation and the startup and shut down of a typical mobile compressor. We will also cover the operation and use of some common pneumatic tools.