Index of patents issued from the United States Patent …
INDEX OF PATENTS *V (J ISSUED FROM HAH THE UNITED STATES PATENT OFFICE 1957 UNITED STATES GOVERNMENT PRINTING OFFICE WASHINGTON For sale by the Superintendent of Documents, U. S.: 1958 Government Printing 06Bce, Washington 25, D. C.-Price $5.50 (Buckram)
2020. 6. 17. 12v switch