An electrical connector includes an insulative housing with a plurality of passageways and a plurality of contacts received therein. The contact includes an upstanding section retained in the passageway with a spring am extending from an upper region of the upstanding plate and above the mating surface, and a mounting leg extending from a lower region of the upstanding plate around the mounting surface. The spring arm forms a contacting section around a free end thereof. The contact further includes an extension extending from the upstanding section and optimally above the mating surface so as to be located between the spring arm and the mating surface in the vertical direction. The extension and the spring arm are partially overlapped in the vertical direction and results in the capacitance effect therebetween, thus lowering impedance.