This is the tertiary module of the USS Vesuvius A

The USS Vesuvius A is a Somma class vessel, typically a cross between a science vessel and a tactical vessel.
The Vesuvius possesses 3 Pegasus Mark II class cloaking devices, as well as the capability to go to Multi Vector Assault Mode.

The USS Vesuvius A has 20 decks

Crew Compliment 400 officers’ 200 civilians. Max capacity 1200 in event of an emergency.

Main engineering is in the tertiary section. (Think all other trek ships) but each section has an engineering section. Main engineering is located on deck 16-17 in the Tertiary section.

The ship has 3 warp cores. The secondary section has Nacelles; technically all three sections have nacelles. The Primary section has them come out the bottom of the saucer. Tertiary has them built in ala Defiant. The ship is MVAM capable with each section having an independent top speed of warp 9.925.
Maximum combined speed it 9.9985.

3 Pegasus Mark II Phase Cloaking devices are included in the Vesuvius’ technical specs.

Main Bridge is housed on Deck 1 of the Primary Section. Each sub section has a battle bridge comparable in size to the main bridge. Main Bridge is the bridge from the first starship Vesuvius that was destroyed by the cardassians.

Main Sickbay is located on deck 3 of Primary Section. Each sub section has an equivalent sickbay located on decks 11 and deck 15.

The ship is armed with Quantum and Photon Torpedoes. Phaser armament includes pulse cannons on the fore of each ship section and the latest in Phaser Bank technology lines the tops and bottoms. Photon Launchers are located at the fore and aft of each ship section.