304 stainless steel pipes. The pipes were used for the passage of air from a remediation process. The pipes were cleaned with water and flushed with air. Some still have sediment, but washing better will clean them. Photo attached. All the pipes were made from 1.5 mm thick tubing bar to which a long spigot was welded at both ends and a PN10 aluminum sliding free flange was inserted. These are the available pieces: 11 pipes L = 6 meters Diameter DN80 Thickness 1.5 mm. 2 pipes L = 6 meters Diameter DN100 Thickness 1.5 mm. 2 pipes L = 2.7 meters Diameter DN80 Thickness 1.5 mm. The pipes can be viewed at our warehouse in Bologna. If you are interested, we can send you more photos/info.