Based on Wookieepedia, the Mandator IV-class Siege Dreadnought, also known as the Mandator IV-class warship and the First Order Dreadnought, was a model of dreadnought used by the First Order during their conflict with the Resistance. It acted as an orbital gun platform, and had access to two orbital guns as well as 26 cannons on the dorsal side, which was comparatively flat. Overall, it was two-and-a-half times the length of the Resurgent-class Star Destroyer. I hope you like it.