Issho (traditional unit of volume, approx. 1.8 liters)

Issho (一升) is a traditional Japanese unit of volume, used mainly for measuring sake. One issho equals approximately 1.8039 liters and is divided into ten go (合). A measure of one issho is commonly used as a serving quantity of sake at restaurants and in homes, and it is also associated with a specific bottle size, the isshobin (一升瓶). This size is convenient for enjoying sake in large quantities and is often used at celebrations and gatherings in particular.