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| Patents for George B. Duffield | |||||
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| Picture | Number | Date | Patentee | Title | |
| 1,629,449 | May 17, 1927 | G.B. Duffield | Valve Operating Device | ||
| 1,661,131 | Feb. 28, 1928 | G.B. Duffield | Expansible Collapsible Element | ||
| 1,719,801 | Jul. 02, 1929 | G.B. Duffield | Valve | ||
| 1,865,560 | Jul. 05, 1932 | G.B. Duffield | Pop Valve | ||
| 2,008,323 | Jul. 16, 1935 | G.B. Duffield | Control Device | ||
| 2,167,433 | Jul. 25, 1939 | G.B. Duffield | Air Vent Valve | ||
| 2,183,488 | Dec. 12, 1939 | G.B. Duffield | Closure | ||