An infusion device (100) comprising an infuser base (105), a cannula (115) anda ferrule (120). The infuser base (105) having a bore (104) extending therethrough,the bore (104) having a distal and proximal ends the proximal end having an insidefirst diameter. A flange (135) extends radially outward from the cannula proximalend. The cannula (115) is positioned in the bore (104) such that the flange (135)is positioned adjacent the shoulder (109). The ferrule (120) has an insertionportion (122), having an outside second diameter which is substantially equalto the first diameter, and a tapered portion (125) extending from the insertionportion (122). The ferrule (120) is positioned in the bore (104) such that theinsertion portion (122) and a portion of the tapered portion (125) are receivedin the cannula proximal end and the flange (135) is compressed between the shoulder(109) and the tapered portion (125) to define a seal (160) between the cannula(115) and the ferrule (120).
