Wow it has been so long since I've seen someone do the classic series. And I've not seen an Interdictor Cruiser since TIE Fighter the game. The Imperial class Star Destroyer is still an awesome sight. Thank you for putting this up. It's good to see the Empire still has a bite!
This is so wonderful... I do wish, however, you would do your own unobtrusive watermark and not use the nasty huge dA watermark right in the center... it is so difficult to see the details of the ship ... It's as if the Mona Lisa had a big fat ugly watermark on it [link]
What SMS00 said, It's an Interdictor Class Star Destroyer.
It was designed to create a gravity well in situations where the currents gravity well of a local celestial body wouldn't be enough to stop a ship from entering hyperspace.
To put it in simpler terms, Interdictors create gravity wells strong enough to completely stop an opposing ship or fleet from escaping into hyperspace.
Interdictor Class Star Destroyers were meant to be part of a support role, they were not really dangerous save for the gravity well generators.. though they did carry a few fleets of tie fighters and maybe a few bombers.