This U.S. industry comprises establishments primarily engaged in (1) manufacturing resins, plastics materials, and nonvulcanizable thermoplastic elastomers and mixing and blending resins on a custom basis and/or (2) manufacturing noncustomized synthetic resins. Cross-References. Establishments primarily engaged in-- ? Manufacturing plastics resins and converting the resins into plastics products--are classified in 3261, Plastics Product Manufacturing; ? Custom compounding resins made elsewhere--are classified in U.S. Industry 325991, Custom Compounding of Purchased Resins; and ? Manufacturing plastics adhesives--are classified in Industry 325520, Adhesive Manufacturing.