An electrical connector includes an insulative housing forming a mating cavity, a plurality of passageways located by two sides of the mating cavity, a bottom cover attached upon a bottom side of the housing to shield the mating cavity in a vertical direction. A plurality of contacts are disposed in the corresponding passageways, respectively. Each contact includes a retaining section retained in the corresponding passageway, a resilient contacting section extending from the retaining section and into the mating cavity, and a leg extending from the retaining section and downwardly through the bottom cover. A waterproofing glue plate is attached upon the bottom cover, and the legs of the contacts extend through the glue plate. The leg forms a transverse groove located in at least one surface and embedded within the glue plate so as to enhance securement between the glue plate and the leg.