Conventional sucker rods (working under torsion loads) are used nowadays to drive PCP pumping systems (Progressing Cavity Pumps). Conventional rods have been developed to work under alternating tensile stress, not under torsion stress. The use of these rods to drive PCP systems has several limitations and problems. These limitations result in high operative costs for artificial lift systems. Also, in many cases the high capacity pumps commonly used today cannot be driven, because of their high torque requirements. Thus PCP pump users require a reliable High Torque rod to drive their systems. This rod must work under high torque stress. The following technical paper refers to the development of the "Hollow Rods" a technical solution tailor made for PCP pumping systems. Different topics covered by this work are: ; General description of this product. ; Design methodology of the connection. ; Laboratory tests (fatigue, destructive tests, etc.) ; Pipe technical specifications. As part of this job, field experience with this product is described. This experience started at October 1999 in Diadema, an oil field operated by CAPSA S. A. Due to the excellent results obtained, CAPSA S. A. decided to extend the installation of Hollow Rods to 70 wells at this oilfield. Today started a third step, were will be installed in another 90 wells during this year. Several advantages of this new technology are: *Lower operating due to the elimination of connection failures. *Less tubing wear. *Increase in pumping rates due to a high torque capacity. *Less initial equipment cost for high displacement pumps compared with ESP. *Possibility to inject different kind of fluids by the inside of the Hollow Rod . I.e. viscosity reduction fluids to pump extra heavy oil, chemical corrosion inhibitors, etc.