Hydrogen is becoming increasingly important among the propulsion technologies for the mobility of the future. To achieve the required energy densities of storage systems for gaseous storage, the mass of high-pressure vessels must be reduced while maintaining or increasing the stored amount of hydrogen. This paper provides an overview of the gravimetric storage density of hydrogen pressure vessels available on the market. The mass distribution of those vessels dependent on the weight of the system components. Subsequently, the individual components and their mass savings potential are determined on different scale levels. Physical effects and associated parameters are deduced. The influences of the different parameters in the levels and their potential for further improving the gravimetric storage density are assessed.