Strain Gage Type K-1

In 1951 (Showa 26), Osamu Watanabe, founder of Kyowa Musen Kenkyujo (now Kyowa Electronic Instruments Co.,Ltd.), started selling Japan's first domestically produced product, the "K-1 strain gage with red felt." At that time, Japan was importing expensive products manufactured in the U.S. and other countries. The gage length of K-1 is 20.5 mm, with a wire diameter of 25 µm and resistance of 120 Ω. The gage is covered with red felt for protection. It was first used in Japan for the measurement of actual deformation stress on ships and contributed to the strong understanding of their strength. The product continues to occupy approximately 50% of the Japanese market share.