wtf is a 34-length PCIe card ??

Mini PCIE to PCI-E Express X1+USB Riser Card with FFC Cable pcie cem slot The VIAVI Solutions 4-lane CEM-slot Interposer for PCIe enables debug and verification of new ICs, new system hardware designs, FPGA firmware, validation of pcie slot dimensions PCI Express Base Specification Rev ; PCIe CEM ; PCI_Express_External_Cabling__06042020_NCB NOTE : Often Sold with our PCIe X8 to GEN 3 with

pcie 30 x1 slot The number after the x tells you how many lanes that PCIe slot has CEM connectors for add-in