Type: Tension Harp > Free-reed > Aerophones.
Region: Borneo > South East Asia.
Gerudeng are tension harps, these are jaw-harps who are activated by pulling a string. Most gerudeng are made from palm stalk, one aluminum example was found. Originally the gerudung were courting instruments they are no longer actively played as most Iban were converted to Christianity.
Citations: Randy Raine-Reusch @ asza.com (Gerudeng Article).