D4x class

In the Kelvin timeline, the D4x class was a Klingon starship class, a battlecruiser-sized bird-of-prey in Imperial Defense Force service in the 2250s decade. In the early 2410s, the primary universe Empire gained access to the D4x class and fielded ships of the class in the KDF. 

History and specifications
The D4x class bird-of-prey was based on the patrol ship. The Klingons were inspired by the tenacious fighter when they designed its starship-sized counterpart. 

A vessel of the class was dispatched by the High Council to Phaedus IV when rogue Captain  offered the Klingons the  flagship USS Enterprise (alternate reality NCC-1701) as prize for turning Phaedus into April's own personal kingdom. The bird-of-prey found the Enterprise in orbit, with April in command. Before the ship could be seized for the Empire, the Enterprise crew ursurped April, and the Federation ship escaped. Phaedus IV was left to the mercy of the Empire instead. 

In 2260, an Alpha Quadrant Alliance starship from the year 2410 of the primary universe was brought to the Delphic Expanse of the Kelvin timeline by Temporal Agent Timot Danlen. The starship helped defend the USS Yorktown (alternate reality) against an attacking swarm of D4x-class birds-of-prey. The Klingons acted as clients of the Sphere Builders. With joined forces, the Federation and the AQA ships destroyed the Klingon raiders. 

Due to the further escalation of the Temporal Cold War, the Federation Temporal Agency made ships of the Kelvin timeline available to the AQA in 2410. Through the Lobi Crystal Consortium, the Klingon Defense Force gained several D4x class birds-of-prey. These were classified as tier 6 pilot bird of prey, a raider class equipped battle cloak and capable of executing pilot maneuvers.

Standard weaponry was rated Mark X. The five weapon slots at the ship's fore were by default equipped with two disruptor dual cannons, a photon torpedo launcher, a dual disruptor beam bank, and a disruptor cannon. A disruptor turret provided the rear firing arc. As a raider - an escort-type class - the ship sported a heavy weapon slot, fitted by default with a Mark XII experimental hyperexcited ion stream projector. Like the proton charge launcher, operated from a universal console, the ion stream projector fired in a 360° arc around the raider.