Abstract: An electrical apparatus in accordance with the present invention for electrically assembling a CPU to a printed circuit board. The CPU includes an array of pin legs. The apparatus comprises a base member securely assembled to the printed circuit board. A cover member is moveably assembled to the base member and defines an array of through holes for extension of the pin legs of the CPU. A driving arrangement is arranged between the base and cover member to drive the cover member to move between first and second positions. The arrangement includes a shaft having a helical section extending therealong, and a follower is moveable along the helical section when the shaft is rotated.