Editing Bird-of-Prey (section)

===Designations===
The Klingons applied several class designations to the different types of their Bird-of-Prey design, including the K'vort-class, B'rel-class and D12-class. 

The D12-class was retired from service by the 2350s due to faulty plasma coils, which were components of the cloaking systems. (Star Trek Generations) In fact, according to Gorta, finding one of these vessels with a working cloaking device was rather unique in 2370. (TNG: "Firstborn") 

By the 2360s, it was not uncommon to find a B'rel-class Bird-of-Prey stripped and relegated to a surplus yard. Ferengi DaiMon Lurin acquired two of these vessels, complete with cloaking devices, and managed to make them space worthy once again, after a few repairs and the addition of some weapons. (TNG: "Rascals") 

In an alternate timeline, the K'Vort-class was referred to as a battle cruiser, and was larger than its "prime universe" counterpart. While slower than the Galaxy-class battleships of the era, in a 3:1 confrontation, a Galaxy-class was not able to last long. (TNG: "Yesterday's Enterprise") This class was known to be equipped with several escape pods, and in use well into the 2370s. (DS9: "Penumbra")