Price is for 25-PACK. Dual-Row 0.1" 2.54mm Socket, IDC, 40 Position, Polarized IDC Flat Ribbon crimp Connectors. These connectors mate with any standard 0.1" spaced dual-row pin headers. The insulation displacement (IDC) contacts on these connectors allow them to be quickly and easily crimped onto flat ribbon cable. These are female sockets designed to connect to male pin headers. These connectors have a polarizing tab in the middle to ensure correct orientation when used with a shrouded header ("box header"). Detailed Description: NUMBER OF PINS: 40P 2x20 IDC SOCKET-RECEPTACLE 0.1" x 0.1" DUAL ROW IDC FEMALE CONNECTOR WITH POLARIZING CENTER BUMP WITH STRAIN RELIEF MATES WITH 0.1" 2.54mm PITCH HEADERS. TERMINATES TO 0.05" FLAT RIBBON CABLE. Includes rear brackets or Strain relief to secure the wiring.