Knapp Polly Pig Inc., the original manufacturer of the Polly Pig, has been manufacturing pipeline cleaners for over 55 years. The company's product lines, in addition to a full line of urethane foam pigs, include urethane cups (conical and scraper), discs, spheres, and several all-urethane pig designs such as the Nova-cast™, Ultra-Seal™, NOVA™, Polly Tri-Cup™, SUD pig, Ultra-Cast™, Polly-Cast™, Foam Disc, Hand-Launch™, Blackbelt™ and K-Disc™. Knapp also supplies steel mandrel assemblies.

Knapp serves the oil & gas, water & wastewater, chemical & food processing sectors of the piping industry. The company specialises in custom designs and materials to suit all applications. Products are available to be used in adverse cleaning situations, pipe size reductions, long distance pig runs, sour gas lines (with H₂S present), automatic pigging operations and other special procedures. The products are available in sizes up to 90 inch, and the company offers assistance to pipeline operators in optimising the cost and efficiency of pigging by analysing their current pigging procedures and making recommendations on improvements.