A finite product made of nonwoven material is obtained and the edges thereof are completely solidified, however the central area remains voluminous. This is achieved by advantageous hydrodynamic hardening devoid of binding agents, whereby the nonwoven material exiting from a nonwoven material placement device, such as a carding device, is initially solidified at least on the surface thereon and previously solidified and re-placeable nonwoven material is fully solidified thereon in a continuous double-stepped hydrodynamic hardening process exclusively along longitudinal strips which are arranged at a distance and over-lapping transversal strips which are also arranged at a distance by means of a plurality of rows of water jets. The nonwoven material is cut after treatment in the positions where full solidification occurs, whereupon products are created.