It is an industrial organisation, functioning under the Department of Defence Production of Ministry of Defence, Government of India.
Ordnance Factories Board (OFB) is the world's largest government-operated production organisation, and the oldest organisation run by the Government of India.
The Board is responsible for manufacturing small arms, missiles, rocket launchers, chemicals, explosives, mines, grenades, anti-tank warfare, etc.
It is often called the "Fourth Arm of Defence", and the "Force Behind the Armed Forces" of India.
OFB is the 37th largest defence equipment manufacturer in the world, 2nd largest in Asia, and the largest in India.
The first Indian ordnance factory can trace its origins back to the year 1712 when the Dutch Ostend Company established a Gun Powder Factory in Ichhapur at West Bengal.
In 1801, Gun Carriage Agency was established at Cossipore, Calcutta.
This is the oldest ordnance factory in India still in existence.