Ultra Clean Holdings, Inc. is a developer and supplier of critical subsystems, primarily for the semiconductor capital equipment industry. The Company also uses the specialized skill sets required to support semiconductor capital equipment to serve the technologically similar markets in the flat panel, medical, energy and research industries, collectively referred to as other addressed industries. It develops, designs, prototypes, engineers, manufactures and tests subsystems, which are specialized and tailored to specific steps in the semiconductor manufacturing process, as well as the manufacturing processes in other addressed industries. Its revenue is derived from the sale of gas delivery systems and other critical subsystems, including chemical mechanical planarization (CMP) subsystems, chemical delivery modules, top-plate assemblies, frame assemblies, process modules and other high-level assemblies. In July 2012, the Company merged with Advanced Integration Technologies (AIT).