Abstract: A disposable assembly and associated method for placing a catheter tube or plastic cannula into the body of a patient, the assembly being initially disposed in a sterile package and comprising a straight or curved hollow cannulated needle sharpened at one end and a connector in the form of a hub at the trailing end thereof, the connector being joined to an elongated semi-rigid sheath having a longitudinal slit along one location. The flexible cannula, having a coiled wire reinforcing the trailing end thereof is initially disposed within the semi-rigid sheath with the leading end thereof resting within the hollow of the needle and the reinforced trailing end within the sheath. A stylet telescopically rests within the entire length of the plastic cannula with the exception of the leading tip thereof and is of such dimension as to stiffen the concentrically disposed plastic cannula.