20mm thick acid pickling tank for aircraft parts20mm thick polypropylene process tanks c/w clear P.V.C inspection windowsSteel reinforcement framework painted and ready for installation over Polypropylene tank body20mm thick polypropylene process tank awaiting insulation and top flange with 9mm thick polypropylene claddingPolypropylene welded joints c/w self adhesive conductive metal tape for high frequency spark testing of weld integrity