An electrical connector, comprising an insulative housing defining a base portion and a mating portion extending from the front side of the base portion along a mating direction; a plurality of passageways disposed in the base portion and extending along the mating direction; a plurality of receiving spaces disposed in the mating portion and communicating with the complementary passageways; a plurality of contacts assembling to the insulative housing along the mating direction, and each contact defining a flat base part mounting to the base portion of the insulative housing and a mating part extending from the base part forwards from the base part and into said receiving space; wherein a spring tab extending downwards from the base part of the contact and locked to the insulative housing.