5188578-1 is a Type A 2mm Hard Metric PCB mount connector plug designed for backplane and midplane applications. It features 154 total positions arranged in 5+2 rows with 110 signal contacts, vertical PCB mounting orientation, and multi-purpose center mating polarization for secure alignment. The connector utilizes gold-plated (30 µm) over nickel (50 µm) contact plating on phosphor bronze contacts with feedthrough posts of 14.50 mm (rows A-E) and 16.00 mm (rows F&Z), housed in gray glass-filled polyester with UL 94V- flammability rating. This connector is RoHS and ELV compliant, making it suitable for CompactPCI applications and high-density interconnect requirements in telecommunications, computing, and industrial equipment where reliable signal transmission and mechanical stability are essential.