In a machine for automatically inserting parallel lead circuit elements into openings in a printed circuit board, the improvement comprising transfer means for selectively gripping and transferring said electronic circuit element, said transfer means including a plurality of chuck means, each said chuck means comprising a fixed block, a first movable block slidably engaged in said fixed block, a second movable block slidably engaged in said first movable block, engagement means for effecting relative movement of said first and second movable blocks with respect to each other, said second movable block including a fixed claw formed thereon, said second movable block further including at least two movable claws disposed thereon, said movable claws including spring biasing means for biasing said movable claws into one of a closed and open position for respectively grpping and releasing said supplied circuit element, and further spring biasing means for bringing said second movable block into engagement with said fixed block to define an open position.