Regarding prosthetic material, meshes have evolved since the first Dacron mesh used by Lichtenstein. First generation meshes were manufactured using more material and for this reason they have been described as heavyweight meshes. New generation meshes have been designed with less material in order to diminish the inflammatory response and foreign body reaction, providing less chronic pain with similar recurrence rates than heavyweight meshes. The density (or weight) of the mesh, measured in g/m2, is inversely proportional to the size of the pore and lately it has been reported that one of the main aspects related to prosthetic materials is pore size. Large pore meshes use less material, consequently they have been associated with a better tissue ingrowth. The large pore of lightweight meshes is conditioned by the less amount of material used.