A socket connector includes an insulative carrier having opposite first and second sides and a plurality of vias extending between the first and second sides. A plurality of polymer columns is held by the carrier. Each polymer column includes a first end extending from the first side of the carrier and a second end extending from the second side of the carrier. A contact array is disposed on each first and second side of the carrier. Each contact array comprises a flexible sheet having a plurality of conductive elements having contact tips proximate corresponding first and second ends of the polymer columns. The conductive elements on the first side of the carrier are electrically connected to corresponding conductive elements on the second side of the carrier through the vias in the carrier to establish electrical paths between corresponding contact tips on the first and second sides of the carrier.