This is most probably the finial from a sacred flute, a highly valued item used during the rituals by which young men were initiated into the secrets of the men's cult (see no. 29, UEA 158).
This long, tubular object has a new wooden mount which blocks a once functional hole at the base. The bottom half of the object is a bamboo tube decorated with a series of thin lines at intervals as well as woven basket detail at the base which has been adorned with red paint.