Bare foam pigs are made from either medium-density (5–7 lb/ft³) or heavy-density (8–10 lb/ft³) polyurethane foam. Medium-density pigs are the most common choice for standard-duty applications, while heavy-density pigs are used for more intensive cleaning or longer runs. They are used for moderate to heavy cleaning and, in some cases, for filling and dewatering pipelines using double-dished models. The uncoated foam body can absorb water or chemicals in the line, while a solid-cast PU seal at one or both ends limits excessive bypass. Available models include bullet-nosed, double-dished (flat on both ends), and double-nosed pigs. Options include tracking cavities, ropes, and cables for handling, lifting, or pulling. Custom sizes and models are available.