Used Nitric Acid Plant Ammonia Air Mixer (Converter Cone). Manufactured by Missouri Boiler and Tank Company, Stainless Steel. Rated 135 psi @ 650 F. Flg "A" 135 psi @ 550 F. Shell thickness 3/16" and 5/16". Head thickness 169 min, Head raidus 211. Serial # H-5235, National Board # 3133, Built 1971. Previous Use: Nitric Acid - Ammonia Air Mixer / Converter (Note: Converter and Converter Elbow not available but drawings are available)