A receptacle connector for mating with a plug connector having a mating tongue and a latch thereof, includes an insulative housing defining a mating slot extending along a longitudinal direction to receive the mating tongue of the plug connector, and an outer metallic shield defining an upper space to receive the latch of the plug connector, and a lower space communicatively below the upper space to receive the housing. A plurality of contacts are disposed in the housing to mechanically and electrically connect to the mating tongue. An inner metallic shield is attached upon the upper wall of the housing to separate the upper space and the lower space from each other in a vertical direction.