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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 = '287') ORDER BY category ASC, date, patent, type

Total of 2 patents found where: Class is '427'; Subclass is '287';

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T / S Patent Date Description Patentee Category Assigned To
 RFI
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.
U 2,281,173 April 28, 1942 Insulator and Method of Producing Conducting Coating Thereon
RFI prevention using an inexpensive glaze coating
SANTOMIERI, Sebastian L.
RFI Victor Insulators, Inc.

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