| 7304 | | Tubes, pipes and hollow profiles, seamless, of iron (other than cast iron) or steel: | | | | |
| 7304.31.60 | 10 | Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters | kg | | | |
| 7304.39.00 | 02 | Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters: | | | | |
| 7304.41.30 | 15 | Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters | kg | | | |
| 7304.41.60 | 15 | Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters | kg | | | |
| 7304.49.00 | 45 | Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters | kg | | | |
| 7304.51.50 | 15 | Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters: | | | | |
| 7304.59.20 | | Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters | | Free | | 35% |
| 7306 | | Other tubes, pipes and hollow profiles (for example, open seamed or welded, riveted or similarly closed), of iron or steel: | | | | |
| 7306.30.50 | 10 | Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters, whether or not cold drawn | kg | | | |
| 7306.40.50 | 15 | Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters, whether or not cold-drawn | kg | | | |
| 7306.50.50 | 10 | Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters, whether or not cold-drawn | kg | | | |
| 7307 | | Tube or pipe fittings (for example, couplings, elbows, sleeves), of iron or steel: | | | | |
| 7307.11.00 | | Cast fittings: | | | | |
| 7307.19.30 | | Ductile fittings | | 5.6% | Free (A,AU,BH,CA, CL,E,IL,J,JO,MA, MX,P, SG) | 45% |
| 7307.19.30 | 40 | Grooved-end fittings (including grooved couplings) | kg | | | |
| 7307.19.90 | 40 | Grooved-end fittings (including grooved couplings) | kg | | | |
| 7307.23.00 | 00 | Butt welding fittings | kg | 5% | Free (A,AU,B,BH, CA,CL,E,IL,J,JO, MA,MX,P, SG) | 45% |
| 7307.93 | | Butt welding fittings: | | | | |
| 7308 | | Structures (excluding prefabricated buildings of heading 9406) and parts of structures (for example, bridges and bridge sections, lock gates, towers, lattice masts, roofs, roofing frameworks, doors and windows and their frames and thresholds for doors, shutters, balustrades, pillars and columns) of iron or steel; plates, rods, angles, shapes, sections, tubes and the like, prepared for use in structures, of iron or steel: | | | | |
| 7308.90.95 | 30 | Sheet-metal roofing, siding, flooring and roof drainage equipment | kg | | | |
| 7309.00.00 | | Reservoirs, tanks, vats and similar containers for any material (other than compressed or liquefied gas), of iron or steel, of a capacity exceeding 300 liters, whether or not lined or heat insulated, but not fitted with mechanical or thermal equipment | | Free | | 45% |
| 7310 | | Tanks, casks, drums, cans, boxes and similar containers, for any material (other than compressed or liquefied gas), of iron or steel, of a capacity not exceeding 300 liters, whether or not lined or heat insulated, but not fitted with mechanical or thermal equipment: | | | | |
| 7311.00.00 | | Containers for compressed or liquefied gas, of iron or steel | | Free | | 25% |
| 7311.00.00 | 30 | Certified prior to exportation to have been made in accordance with the safety requirements of sections 178.36 through 178.68 of title 49 CFR or under a specific exemption to those requirements: | | | | |