The siamang (Symphalangus syndactylus) is an arboreal, black-furred gibbon native to the forests of Indonesia, Malaysia, and Thailand. The largest of the gibbons, the siamang can be twice the size of other gibbons, reaching 1 m (3.3 ft) in height, and weighing up to 14 kg (31 lb). The siamang is the only species in the genus Symphalangus.