Stacked electrical card connector assembly

A stacked electrical card connector assembly mounted on a PCB for interconnecting inserted electrical cards with the PCB, comprising:

• an upper connector having an upper header, the upper header comprising an insulative main body and a metallic shield covering the main body, a plurality of first signal contacts being received in the main body;
• a lower connector having an insulative lower header, a metallic lower frame assembled to the lower header, and a contacting module having an insulation block with a base portion, the contacting module being assembled to the main body of the upper header and having a plurality of second signal contact defined under the first signal contacts, the lower frame having a opening defined at one end opposite the lower header thereby defining a receiving space to receive a part of the contacting module therein;
• a transition device having a first contacting portion, the first contacting portion having a plurality of solder holes respectively receiving the first and second signal contacts therein;
• wherein
• the transition device comprises a transition printed circuit board and has a second contacting portion connected with the first contacting portion, the second contacting portion being connected with a mating connector mounted on a PCB;
• wherein
• the main body has a pair of latches, and a pair of locating holes is defined in the base portion of the contacting module and engage with the latches, thereby securing the contacting module to the upper header.