An electrical connector assembly (100) comprises an insulative housing (1) comprising a lower wall, a receiving space (110), a cavity (120) above the receiving space (110), a shielding shell (9) enclosing the insulative housing (1), a number of contacts (2, 3) received in the insulative housing (1) and a cable (5). The contacts (2, 3) comprise a number of first contacts (2) for transmitting USB 3.0 signal and a number of second contacts (3) capable of transmitting USB 2.0 signal, and an extra signal contact (3e) transmitting an extra signal. The second contacts are partly received in the receiving space (110). The first contacts are partly received in the cavity (120). The engaging section of the extra signal contact (3e) is located on an inner surface of the lower wall.