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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 = '200') AND (category.subclass = 'DIG.4') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '200'; Subclass is 'DIG.4';

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T / S Patent Date Description Patentee Category Assigned To
 1924
U 1,501,732 July 15, 1924 Column Strain Insulator
Electrose strain insulator		 STEINBERGER, Louis
 Strain  

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