Electrical connector assembly

An electrical connector assembly for electrically connecting a daughter board to a mother board, comprising:

• a receptacle connector being mounted on a mother board and including
• a first insulative housing having a first body portion and a first side wall projecting upward from a side edge of the first body portion, the first side wall defining at least two first holes, and
• two rows of first terminals being retained in the first insulative housing;
• and
• a plug connector being mounted on a daughter board and rotatable to mate with the receptacle connector, the plug connector including
• a second insulative housing forming at least two second embossments on a lateral side thereof for latching into the at least two first holes of the receptacle connector, and
• two rows of second terminals being retained in the second insulative housing for mating with corresponding first terminals of the receptacle connector;
• wherein
• the first body portion of the first insulative housing defines two rows of first passageways in a top face thereof, and a recess below and communicated with each first passageway;
• wherein
• each first terminal has a retaining portion retained in the first insulative housing, a mating portion extending from one end of the retaining portion into a corresponding first passageway of the first insulative housing, and a horizontal soldering portion extending from another end of the retaining portion for soldering to the mother board;
• wherein
• the mating portion of the first terminal has a tip end for being received into a corresponding recess of the first insulative housing when the receptacle and plug connectors are fully mated with each other;
• wherein
• the plug connector is similar to the receptacle connector in structure;
• wherein
• the first body portion of the first insulative housing further forms at least two projections on a lateral side thereof opposite to the first side wall.