A device for treating fluids, such as automotive exhaust gases is provided, as well as a method of manufacturing such a device. The device provides a honeycomb structure, a matrix of ceramic walls that defines a plurality of parallel, fluid-conducting cells oriented along an axis, arranged in a stacked or discontinuous configuration between an inlet and outlet, where adjacent layers of honeycomb structure are separated by layers of air spaces. Each matrix layer has opposing faces that defines the inlets and outlets of the cells, and a peripheral portion or peripheral region including an outer skin. The peripheral portions or peripheral regions of adjacent stacked ceramic layers are mutually contiguous to prevent fluid flowing through the stacked ceramic layers from leaking between said outer skins.