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1 result for “Owens-Illinois”

1. Patent · April 30, 1957

   Filter demonstration device (US Patent 2,790,253, 1957)

   …30, 1957, filed July 30, 1953. The patent's description opens (from the scanned text): This invention relates to a demonstration device and, more particularly, to a demonstration device for demonstrating the efliciency of filter materials.