It has a blade about 6 inches (15 cm) long, counting the curve, and about 4 inches (10 cm) tall.
It is bevelled on one side.
The handle is on top of the blade; the handle can be made of wood, plastic or bone. The design puts the force of your hand directly above the centre of the blade. With traditional knives, the force is at the end of the blade.
Like a mezzaluna, it can be rocked back and forth for mincing, but it has more functionality than a mezzaluna: it can be used for cutting, chopping, slicing and scraping.
When sharpening, sharpen only the bevelled side.
An Ulu Knife is based on a traditional knife used by the Inuit, though of course instead of the blade being steel, they had blades of slate, iron or copper. They used it for everything, not just food: cutting and scraping skins for clothing, etc.