JTOPTICS 400G QSFP-DD DAC (Passive Direct Attach Copper) enables high-bandwidth 400G links and supports 400G Ethernet rate. It is high-speed, cost-effective alternatives to fiber optics in 400G Ethernet applications. The 400G QSFP-DD DAC cable contains 16 high-speed copper pairs, each operating at data rates of up to 53Gb/s, which are suitable for very short links and offer a cost-effective and power-efficient way to establish a 400-Gigabit link between QSFP-400G ports of switches/routers within racks and across adjacent racks. They enable higher port bandwidth, density and configurability at a low cost and reduced power requirement in the data centers. Hot-pluggable QSFP-DD form factor Data rate up to 425Gbps.8x 53Gb/s PAM4 modulation QSFP-DD MSA, CMIS and IEEE 802.3 compliant Operating case temperature of 0-70℃ Copper link length up to 3m Single 3.3V supply voltage Bit Error Rate (BER) better than 1E-15 RoHS compliantData rate up to 53.125Gbps ..