Since 1957, Stenner has produced performance reliable chemical feed pumps. One of the many benefits of Stenner's modular design is easy configuration to meet specific output requirements for a wide variety of applications. Simplicity makes the difference! The Classic 45 Series Adjustable Pumps are single head self-priming pumps that have adjustable outputs. The gear driven motor is 26 RPM. The Peristaltic advantage includes: automatic degassing, self-priming against pressure, and can prime up to 25 feet.