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. 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.