Specification and commercial drainage products are designed for use in DWV (drainage, waste, and vent) systems within commercial, institutional, and industrial buildings, where performance, durability, and code compliance requirements are important. These items are typically selected for a job by engineers or mechanical contractors and often require submittals and approvals. Products are generally manufactured from durable materials, including cast iron, ductile iron, and engineered polymers to provide a long service life in demanding applications.