| 1965 HARRY Tear Duct Sleeping Doll Eye Patent |
| 1969 GARDINER Variable Area Duct Patent Print |
| 1969 US NAVY Thruster Duct Nozzle Patent Print |
| 1946 HUNTER WILLSON Duct Throttle Patent Print |
| 1948 WALLER Air Duct System For Aircraft Patent |
| 1956 BRITTON Cooling Duct Arrangement Patent |
| 1943 JOHNSON CLARENCE Anti Icing Duct Patent |
| 1946 JOSEPH LEDWINKA Heater Duct Patent Print |
| 1929 MAX Sound Duct For Talking Machines Patent |
| 1965 HARRY Restricted Tear Duct Doll Eyes Patent |
| 1959 HUCH Duct Appendix Balloon Patent Print Art |
| 1963 GLASSMAN Common Bile Duct Probe Patent 40241 |
| 1953 MESSINGER Supercharger Duct System Patent |
| 1946 GOODRICH CO B F Duct Throttle Patent Print |
| 1969 THOMAS Thruster Duct Nozzle Patent Print |
| 1937 AMERICAN RADIATOR CO Duct Patent Print Art |
| 1946 BUDD EDWARD G MFG CO Heater Duct Patent |
| 1967 GARDNER Ornamental Design Urinal Duct Patent 40316 |
| 1937 LAMBERT Duct Art Print Patent |
| 1923 LUDWIG Gas Duct In Airships Patent Print |
| 1962 FROEHLICH Valving Duct Balloon Patent Print |