Batlh class

The Balth-class was a Klingon starship class, an escort vessel in service to various Great Houses of the Klingon Empire in the 2250s decade. (,, (Star Trek:

Service history
Following roughly a century of relative peace, the Federation encountered Batlh-class escorts when the Starfleet starship USS Shenzhou, and its reinforcements, was attacked by representatives of 24 Klingon Great Houses at the Battle of the Binary Stars on May 11, 2256. The battle had been instigated by the fanatic T'Kuvma to reunite the Empire by rallying its houses against a common foe. 

Ships of this class active around the years 2256-2257 and saw action against the Federation military and civilians in the Federation-Klingon War of 2256-2257. 

Specifications
When the Klingon Empire was in disarray, ships of the Batlh class were fielded by several Great Houses, rather than the Klingon Defense Force. The vessel's design was defined by a elongated primary hull, topped with a spine and ending in a rounded saucer-like section, flanked by comparatively large warp nacelles. 

Ships of the class were rated escorts. During the Federation-Klingon War of 2256-2257, Batlh-class starships were equipped with cloaking devices developed by the House of T'Kuvma.