An electrical connector comprises an insulative housing having a base portion, a tongue portion extending forwardly from the base portion, the tongue portion being thinner than the base portion; a metal shell attached to the base portion to enclose the tongue portion to define a receiving room therebetween; a plurality of contacts including a plurality of first contacts and a plurality of second contacts, the first contacts each defining a first contacting arm and a first soldering leg, the second contacts each defining a second contacting arm and a second soldering leg; and wherein the first soldering legs and the second soldering legs are arranged in one row, the contacts at least include a first pair of differential contacts adjacent to each other, a second pair of differential contacts adjacent to each other, a pair of ground contacts adjacent to each other and positioned between the first pair of differential contacts and the second pair of differential contacts.