This U.S. industry comprises establishments primarily engaged in manufacturing plastics or fiberglass plumbing fixtures. Examples of products made by these establishments are plastics or fiberglass bathtubs, hot tubs, portable toilets, and shower stalls. Cross-References. Establishments primarily engaged in-- ? Assembling plastics components into plumbing fixture fittings, such as faucets--are classified in U.S. Industry 332913, Plumbing Fixture Fitting and Trim Manufacturing; and ? Manufacturing plastics pipe and pipe fittings--are classified in U.S. Industry 326122, Plastics Pipe and Pipe Fitting Manufacturing.