The radial artery pulse is palpated carefully just above the radial styloid process and the radial artery is fixed between the middle and index finger of left hand of operator and have a mental makeup of radial course between two fingers. 20G Jelco is used for puncturing the radial artery. 2-.3 ml of 2% Xylocaine is injected subcutaneously over the puncture site after pinching the  skin of local area and a bleb was produced. Now 20G Jelco with beveled end upward is used to puncture at 20 -30 angulation. Once the radial artery Is punctured, a gush  of blood will come to needle hub of Jelco. Then counter puncture  is done to transfix the radial artery. The needle is withdrawn from the cannula. After that the cannula  is very slowly withdrawn keeping it horizontal to patients arm. Once the  arterial blood comes out of the cannula, a 0.25 short Terrumo wire (supplied with Terrumo punctured kit) is introduced through  the cannula  to radial artery. A small nick done over the skin and the Terrumo puncture kit (5F for diagnostic purpose and 6F for intervention) was introduced over the wire. The dilator and wire withdrawn and radial punctured was established.