A device for facilitating the act of connecting a service line to a flowing main line. A gate type valve is rigidly attached to the main line and a barrel is removably affixed to the valve and is adapted to cooperate with a mandrel which includes a shaped charge at one extremity thereof. The mandrel cooperates with the barrel to enable the shaped charge to be positioned adjacent the main line, whereupon the explosive shaped charge perforates the main line when a detonator is activated. The mandrel is retrieved along with the barrel to enable further use of the device. The invention also comprehends a mandrel that can be affixed between the gate valve and the flowing main line by including a recoil device in conjunction therewith. The invention further includes a shaped charge that is adapted to be fabricated into the ball member of a ball type valve.