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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 = '427') AND (category.subclass = '279') ORDER BY date ASC, patent, type

Total of 2 patents found where: Class is '427'; Subclass is '279';

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T / S Patent Date Description Patentee Category Assigned To
U 1,784,392 December 9, 1930 Manufacture of Insulators
Suspension insulator with glazed sanded surfaces to improve strength of cap
ROWLAND, Davidge H.
Suspension Locke Insulator Corp.
U 1,987,683 January 15, 1935 Insulator
RFI: coat crown with copper glaze to prevent AM radio interference
HUNT, Marsden H.
BARROW, George M.
RFI Westinghouse Electric & Mfg. Co.

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