Umbul-umbul

Umbul-umbul, also called rérontek or, archaically, tunggul,[1] are a type of flag or pennant made of a strip of cloth whose longer side is attached to a pole.

[2] They are used in the traditional culture of Java and Bali, Indonesia, where they are carried in festivals[3] and serve other decorative purposes.

Red and white Umbul-umbuls are raised throughout Indonesia along streets in August to commemorate the Indonesian independence day.

Traditional umbul-umbul in Java and Bali are usually curved, because they are posted on bamboo poles which are flexible and swing in the wind.

A Sundanese language dictionary of 1862 translates the word "umbul-umbul" as "a banner; any signal, as a flag or other object, hoisted so as to be seen at a distance.