A nambas is a traditional penis sheath from Vanuatu

Vanuatu

Vanuatu , officially the Republic of Vanuatu , is an island nation located in the South Pacific Ocean. The archipelago, which is of volcanic origin, is some east of northern Australia, northeast of New Caledonia, west of Fiji, and southeast of the Solomon Islands, near New Guinea.Vanuatu was...

. Namba are wrapped around the penis

Penis

The penis is a biological feature of male animals including both vertebrates and invertebrates...

 of the wearer, sometimes as their only clothing. Two tribes on Malakula

Malakula

Malakula Island , also spelled Malekula, is the second-largest island in the nation of Vanuatu, in the Pacific Ocean region of Melanesia...

, the Big Nambas and the Smol (Small) Nambas, are named for the size of their nambas.

Nambas are characteristic of central Vanuatu. In northern islands, long mats wrapped around the waist are worn instead.