Sector 004 on a mission order
Sector 004 was a region of space. This sector contained a partial segment of the Romulan Neutral Zone, which was located in section 11. In 2364, the Federation starships USS Tranquillity Base, USS Non Sequitur, and USS Max Plank were ordered by Starfleet Command to decrease sensor drone surveillance of this sector. (TNG: "Conspiracy", display graphic)
According to the Star Trek: Star Charts (pg. 19), the Sigma Draconis system was located in this sector, which was also known as the Sigma Draconis sector.