An excellent Kiphoko helmet mask from the East Pende in the DR Congo.
Helmet mask with a flat, projecting lower edge. It is enhanced with red, black and white pigment and decorated with triangular motifs on the neck and rim. The distinctive nose protrudes at a right angle to the face, the eyes are ovoid, and the ears stick out from either side of the head.

Phoko means knife or sword. Kiphoko refers to the sword user or executioner (ngunza). But the kiphoko mask represents the chief of the community whose formidable character is symbolized by the swords held by the masked dancer. This mask plays a very important role in the life of the Pende living in Kasai. It is linked simultaneously to the power of the chief-even forming one of his attributes, to circimcision rites (mukanda), and to the ancestor cult relating it to variuos aspects of Pende life. It is said that the mask's absence can cause all sorts of disasters.
Source - For Spirits and Kings - African Art in the Tishman collection - Susan Vogel (Ed.)