The Abu al-Fadhel al-Abbas Brigade is a pro-government shi'ite militia active in the syrian civil war. The group is named after Abbas ibn Ali, the some of Imam Ali and important figure in shi'a islam in his own right.
The official reason for its formation was to defend Shi'a holy sites against desecretion by members of ISIS as the later view shrines and similar sites as being a form of idolatry.
A similarly named organisation, The Abu al-Fadhel al-Abbas Forces, exist in Iraq although while it claims link with the syrian group, it wears a different patch and do not appear to share the same chain of command.
members of the brigade wear military garbs from a variety of origin with the only common identifier being a large rectangular patch embroidered gold on black worn on the upper left arm. It shows a gold rectangular outline around some text on 3 lines which, translated from the arabic, reads: “The servants of Al-Set Zaynab, Abu al-Fadhel al-Abbas Brigade, may peace be upon them"