CB,CBI Series CB and CBI series of pumps are horizontal,multistage centrifugal pumps, with the impellers mounted on the motor shaft. The pump housing is attached to a base plate. The design makes the pump suitable for installation in small spaces. A high quality mechanical seal is included as a part of the pump. CB: The discharge and suction chamber are made of cast iron. All other pump parts in contact with the liquid are made of stainless steel. CBI:All parts of pump in contact with the liquid are made of stainless steel.