Number | Name | Date | Kind |
---|---|---|---|
24660 | Potts | Jul 1859 | |
D314820 | Sullivan | Feb 1991 | |
567231 | Glauber | Sep 1896 | |
925762 | Eager | Jun 1909 | |
2086007 | Tompkins | Jul 1937 | |
2215318 | Bristol | Sep 1940 | |
4773197 | Sullivan | Sep 1988 |
Entry |
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Exhibit A--Photograph of prior air duct riser. |
Exhibit B--Photograph of prior air duct riser. |
Sales information from Northern Pipe Products and GPK Products, Inc. (Undated but believed to be prior art to the present application). |
Number | Date | Country | |
---|---|---|---|
Parent | 852094 | Mar 1992 |