Flexible duct for bioleaching process. Diameter from 400 mm. to 1200 mm. Stainless steel rings at the ends. Includes stainless steel collar. Base material: Made of 1.2 mm black PVC coated polyester fabric of high resistance. On both sides, anti-static, flame retardant and UV protection. Suitable for environments contaminated with sulfuric acid. Electronically sealed by high frequency.