Abstract: An interface includes a blast plate having plate structure, the plate structure being formed to substantially conform to a certain portion of an exterior margin of a hull of a certain vehicle and being semi-permanently mounted to the hull by mounting to certain mounting devices present on the exterior margin of the hull and having mounting means for supportively mounting a standardized add-on device, the mounting means being designed to facilitate the add-on device being readily mountable on and demountable from the plate structure, the plate structure having structural characteristics for acting to protect the hull from effects of a blast directed at the hull. A modular assembly and a blast plate are further included.