In the magazine of Gineco Obstetricia de México, January 1988, 30 to 34, I presented the three first models of the Salas forceps. In this article I describe the fourth and last design of my invention which has been patented in the USA as "Salas Obstetric Spatulas". It is mentioned in this article, the advantages of this instrument, which after being used in 533 applications by Dr. Fernandez del Castillo, SC and Dr. Viesca, MA they have come to the conclusion that the Salas instrument is excellent. Laufe et al in his book describe: There is no doubt that these forceps (Salas) could be made more acceptable to US practitioners. It is insisted in the modern classification of the forceps.