Alternate Reality(split 2233)
The Mayflower-type was a medium-sized starship class in service to Starfleet in an alternate reality in the mid-23rd century. A typical ship of this type had two nacelles connected to the underside of the primary hull by swept pylons. This type participated in the pivotal Battle of Vulcan in 2258, and was named after the USS Mayflower. (Star Trek)
In the Blu-ray special "Starships" a ship of this type is labeled as the USS
Defiant (NCC-1764) (β). Additionally, the ship is drawn with a roll bar similar to that of the Miranda-class.
The Gizmotron models 1/2500 scale model kit names this ship type as the Federation frigate.