Manuscript is dedicated to the cartridges on the base of micro-fibrous catalysts. Under the strong influence of external diffusion limitations, the structured cartridges with glass-fiber catalysts (GFC) demonstrate the performance at least not worse than that of the most efficient types of conventional catalysts in volumetric apparent activity, significantly exceeding them in apparent reaction rate per unit mass of the active component or per unit pressure drop, making the GFCs one of the most efficient shapes among all existing catalytic structures. The newly proposed lemniscate-shaped GFCs demonstrate the best performance among all studied systems. The intrinsic kinetics, internal and external mass transfer intensity were studied using the model reaction of toluene deep oxidation in air at Pt-containing GFC. The elaborated criterial equation provides calculation of the external mass transfer coefficient in such catalysts with acceptable accuracy. Mass transfer enhancement in GFC cartridges is explained by flexibility of fibrous supports, resulting in the change of their shape and increase of their effective external area under the influence of the, moving reaction fluid. Such systems look promising for application in fast catalytic reactions, occurring under strong influence of diffusion limitations in gas, liquid and multiphase media.