Tun
The tun is a historical unit of volume used primarily for measuring large quantities of liquid, especially wine or other alcoholic beverages.
Traditionally, 1 tun โ 252 US gallons (about 954 liters)
It was used in shipping and storage of liquids in large barrels called "tuns."
Summary:
1 tun โ 252 US gallons โ 954 liters
Mainly used historically for wine and spirits
Represents a large cask or barrel volume in trade and storage