Receptacle connector

A receptacle connector, comprising:

• a first terminal assembly including a first housing and a plurality of first terminals integrated with the first housing, the first terminals being arranged in horizontal transverse direction in front of the first housing and being arranged in vertical front and rear rows under the first housing;
• a second terminal assembly including a second housing and a plurality of second terminals integrated with the second housing, a rear of a bottom face of the second housing protruding downward to form an extending portion, the second terminals being arranged in horizontal transverse direction in front of the second housing and being arranged in horizontal transverse direction under the extending portion, the second terminal assembly being mounted downward onto the first terminal assembly, wherein the second housing is fastened upon the first housing, the extending portion is positioned in rear of the first housing, the second terminals are located over and behind the first terminals;
• a tongue board assembly mounted between the first terminal assembly and the second terminal assembly, the tongue board assembly including an insulating body and a middle shielding sheet integrated with the insulating body, a rear of the middle shielding sheet being clamped between the first housing and the second housing, the insulating body being located in front of the first housing and the second housing to position the first terminals and the second terminals into a bottom face and a top face of the insulating body respectively;
• an insulating housing having a base portion molded outside the first housing, the rear of the middle shielding sheet and the second housing, a front face of the base portion protruding frontward to form a tongue board molded outside the insulating body together with the first terminals and the second terminals, front ends of the first terminals and the second terminals being respectively exposed outside top and bottom faces of the tongue board, tail ends of the first terminals and the second terminals projecting beyond a bottom face of the base portion;
• and
• a shielding shell worn around the insulating housing;
• wherein top and bottom faces of a front of the tongue board define a pair of butting grooves, the front ends of the first terminals and the second terminals are exposed in the butting grooves of the tongue board.