This document provides information about concrete mixers. It begins with an introduction describing a typical concrete mixer as using a revolving drum to mix cement, aggregate, and water into uniform concrete. It then classifies mixers as either continuous or batch. Continuous mixers produce concrete continuously, while batch mixers produce concrete in batches. Batch mixers are further classified as drum mixers, pan mixers, tilting drum mixers, reversing drum mixers, and transit mixers. Technical specifications are provided for different models of drum mixers. Transit mixers are described as transporting mixed concrete to construction sites while continuing to agitate the mixture.