The plurality of the conductive terminals 20 include an upper row of the conductive terminals 20 and a lower row of the conductive terminals 20. Each of the plurality of the conductive terminals 20 has a fastening portion 21, an extending portion 22 connected with a front end of the fastening portion 21, a contact portion 23 connected with a front end of the extending portion 22, and a soldering foot 25 connected with a rear end of the fastening portion 21. Rear ends of the upper row of the conductive terminals 20 and the lower row of the conductive terminals 20 project beyond the rear surface of the insulating housing 10. Front ends of the upper row of the conductive terminals 20 pass through the upper row of the terminal grooves 124 and are exposed to one of the two opposite docking surfaces 101. Front ends of the lower row of the conductive terminals 20 pass through the lower row of the terminal grooves 124 and are exposed to the other docking surface 101.

The fastening portions 21 of the plurality of the conductive terminals 20 are integrally molded in and fastened in the main portion 11 of the insulating housing 10. The extending portions 22 of the plurality of the conductive terminals 20 are received in the terminal grooves 124 and exposed out of the insulating housing 10 through the terminal grooves 124. A surface of the extending portion 22 of each of the plurality of the conductive terminals 20 is coated with a layer of insulation ink by a pad printing technology to form an insulation layer 24.