The Cisco QDD-400-CU3M is a 3-meter passive copper Direct Attach Cable manufactured by Cisco. It features QSFP-DD connectors on both ends and supports data transmission speeds up to 400 Gbps, suitable for short-range high-speed interconnects in compatible systems.

This cable supports point-to-point connections between QSFP-DD ports within network switches or other hardware requiring direct physical links at standard rack distances. As a passive copper variant, it requires no external power source and has low latency properties due to its electrical signaling design. The form factor aligns with the requirements of high-density port configurations using eight-lane (8x50Gbps) transceivers under the current Ethernet standards.

Cisco QDD-400-CU3M: 400G QSFP-DD Transceiver, Passive Copper Cable, 3 meters