A day for bagged ice, specifically "Rock Ice"

Today, and June 9th annually, is Rock Ice Day ロックアイスの日 in Japan. The anniversary was established by a company, Kokubo Ice & Refrigeration Co., Ltd., that are known for manufacturing ice products, including bagged ice. They call their bagged ice "Rock Ice". Hence, they chose June 9th as the date of the anniversary, because 6/9 can be read as "ro (6) kku (9)". 

The goal of the anniversary is to help more people discover the convenience and versatile uses of Rock Ice, the company’s flagship item. It is a high‑quality cubed ice, developed through their own pioneering manufacturing methods within the ice industry. It is known for its exceptional clarity and clean appearance, making it visually appealing in drinks and cocktails. “Rock Ice” is both a product name and a registered trademark of the company.

Reportedly, the product was inspired by bagged ice sold in Hawaii. The product was introduced in Japan in 1973 and remains a familiar sight in supermarkets across Japan. We find it very useful at this time of year for cooler boxes when going on barbecues and / or camping trips. Do you ever use "Rock Ice"?