5646442-1 is a 2mm Hard Metric (Z-PACK 2mm HM) PCB mount receptacle connector designed for backplane and midplane applications. This Type D, 25-column connector features 176 positions arranged in 8 rows with a right-angle PCB mount orientation and ACTION PIN post signal contacts. The connector utilizes phosphor bronze contacts with gold (30) over nickel (50) plating in the mating area and tin over nickel termination end plating, housed in a gray glass-filled polyester housing with UL 94V-0 flammability rating. With a module length of 48.00 mm and CompactPCI compatibility, this RoHS compliant connector is ideal for high-density interconnect solutions in telecommunications, computing, and industrial equipment.