Side 1: MCIO SFF-TA-1016 8X 74Pin ^^ Side 2: 2 x U. 2 SFF-8639 with 15pin SATA power ^^ PCIe 4.0 Gen4 85-ohm ^^ Silver plated AWG30 Twinax for impeccable signal integrity ^^ The compact design is suitable for installation in confined spaces, such as servers or workstations.