Essential for a high success rate in peripheral nerve blocks is the identification of the correct puncture site. Up to now, the most important techniques for positioning the puncture of the needle have primarily been the location of anatomical landmarks, the feeling of fascial 'clicks' upon insertion of the puncture needle into the vessel/nerve sheath, the triggering of paresthesia (sensation of pain upon contact with the nerves) and electrical nerve stimulation. With the REGANESTH® duoplex, we present a plexus needle which combines the established methods of electrical nerve stimulation with ultrasound imaging of the needle. This makes a consequential addition to our actual portfolio of instruments for peripheral regional anaesthesia.