Alam

This is an 'alam. When it was used, it would have been mounted on a wooden pole (to make it even taller!). It was carried in processions during Ashura, a day of remembrance on the 10th of Muharram, the first month of the Islamic calendar. Ashura commemorates the Battle of Karbala (AH 61/AD 680) and the martyrdom of al-Husayn bin 'Ali, the grandson of Prophet Muhammad and the third imam of Shi'a Muslims.
The base of the 'alam is a pierced cube with invocations to the Prophet. The two pear-shaped panels in the middle are decorated with religious inscriptions and dragon ornaments. Rising above is a finial inspired by the sword of 'Ali.
See it on display on Level 2 at ACM (Asian Civilisations Museum). Made in early 18th-century Iran, during the Safavid dynasty.