OKUI Rishiri Kombu for Dashi Broth, Premium Quality, 150g

This Rishiri Kombu is of exquisite quality and used by many high class restaurants in Kyoto. It makes a very elegant and transparent soup. We recommend immersing it in the soup's water for 8 to 12 hours and then remove it before cooking as it might otherwise leave an unpleasant flavor and turbidity. After opening please store the kombu in a dry environment (e.g. tupper ware). White powder might sometimes appear on the surface of the kombu sheets. This is umami and is perfectly normal! 
The Rishiri kombu comes in 1-cut. About 30g is recommended for 1L of stock. 

Japan's Best Kombu Kelp Producer

The company Okui Kaiseido has been established in 1871 and is now run by the fourth generation of the Okui family. The company is located in Tsuruga, which at the time of the establishment was one of the main ports used to trade Kombu kelp from Hokkaido to Osaka and Kyoto. Nowadays, there are very few makers that understand and master this traditional art. Mr. Okui is one of these makers and therefore the Kombu from Okui Kaiseido is well-known and often chosen by famous Japanese chefs.