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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent LEFT JOIN category ON category.patent = patent.patent AND category.type = patent.type WHERE (category.class = '425') AND (category.subclass = '392') ORDER BY date ASC, patent, type

Total of 3 patents found where: Class is '425'; Subclass is '392';

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T / S Patent Date Description Patentee Category Assigned To
U 1,342,053 June 1, 1920 Bushing Forming Machine
Machine to manufacture wall tubes and bushings
Wall Tube Brunt Tile & Porcelain Co.
U 1,381,695 June 14, 1921 Porcelain Tube Heading Machine
Machine for making wall tubes
BEATTY, Thomas W.
Wall Tube  
U 1,469,584 October 2, 1923 Tube Forming Machine
Machine for making porcelain wall tubes
CASE, Francis M.
Wall Tube Federal Porcelain Co.

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