The grmavica marked with the inventory number Et 9765(a-e), also called germjavica on the island of Krk, is the simplest type of aerophone, without a pipe. It is composed of five small wooden slats joined together with a cord which is run through a little hole pierced close to the edge of one wooden slat. Sound is produced in the manner that the performer very rapidly spins the wooden slats directly above their head, thus rendering a sound resembling rolling thunder (grmljavina) – precisely after which the instrument was named.

In the past the germjavica was found “ different cultures all over the world and was used as a powerful magic tool for invoking rain and warding off evil forces. Nowadays, along with some other simple instruments, it is a children’s toy” (Ćaleta, 2001: 432).