An electrical connector includes an insulative base and an insulative cover moveable relative to the base along the front-to-back direction. A lever includes an actuating bar sandwiched between the base and the cover and is rotated to move the cover relative to the base. A metallic reinforcement piece is embedded within the base adjacent to the actuating bar. The metallic reinforcement piece includes a main part in compliance with a receiving groove of the base receiving the actuating bar therein, and a pair of wings at two opposite transverse side edge of the receiving groove.