| 34140 | Undec-10-enoic acid | |
| 35230 | Undecalactone | |
| 34170 | Undecanal | |
| 34170 | Undecylenic aldehyde | |
| 27921 | Undercarpets, felt, coated, impregnated, covered or laminated | |
| 27921 | Undercarpets, felt, not impregnated, coated, covered or laminated | |
| 49640 | Undercarriages, aircraft | |
| 87141 | Undercoating of motor vehicles | |
| 85210 | Undercover investigation services | |
| 28250 | Undergarments (excl. corsets, brassières, girdles and the like), knitted or crocheted of fabrics of subclasses 27997 and 36250 | |
| 28227 | Undergarments, babies', knitted or crocheted | |
| 28235 | Undergarments, babies', not knitted or crocheted | |
| 32193 | Undergarments, of paper or cellulose wadding | |
| 54252 | Underground cable television lines, general construction of | |
| 28227 | Underpants, babies', knitted or crocheted | |
| 28235 | Underpants, babies', not knitted or crocheted | |
| 28222 | Underpants, men's or boys', knitted or crocheted of textile materials | |
| 28232 | Underpants, men's or boys', not knitted or crocheted | |
| 28224 | Underpants, women's or girls', knitted or crocheted of textile materials | |
| 28227 | Undershirts, babies', knitted or crocheted | |
| 28235 | Undershirts, babies', not knitted or crocheted | |
| 28225 | Undershirts, knitted or crocheted (excl. babies') | |
| 28232 | Undershirts, men's or boys', not knitted or crocheted | |
| 28210 | Understockings, knitted or crocheted | |
| 83391 | Undertaking contamination studies of agricultural buildings | |
| 83392 | Undertaking contamination studies of airfield runways | |
| 83392 | Undertaking contamination studies of bridges | |
| 83393 | Undertaking contamination studies of chemical and related facilities | |
| 83392 | Undertaking contamination studies of civil engineering works | |
| 83391 | Undertaking contamination studies of commercial buildings | |
| 83392 | Undertaking contamination studies of dams | |
| 83392 | Undertaking contamination studies of elevated highways | |
| 83392 | Undertaking contamination studies of harbours | |
| 83392 | Undertaking contamination studies of highways | |
| 83391 | Undertaking contamination studies of industrial buildings | |
| 83393 | Undertaking contamination studies of industrial plants and processes | |
| 83392 | Undertaking contamination studies of irrigation works | |
| 83392 | Undertaking contamination studies of local cables and related works | |
| 83392 | Undertaking contamination studies of local pipelines and related works | |
| 83392 | Undertaking contamination studies of long-distance communication lines | |