Cisco QDD-400-CU2.5M Compatible 400G QSFP-DD 8 x 50G PAM4 Passive Copper Twinax Cable, 2.5m (8ft)

The HT-manufactured QDD-400-CU2.5M compatible cable provides 400G connectivity for Cisco equipment. This 2.5m (8ft) version is a factory-terminated passive copper link without separate optical modules or patch cords, with an exact part number and length that can be matched directly to the equipment requirement.

OEM Part Number: QDD-400-CU2.5MHT Part Number: QDD-400-CU2.5M

Product Highlights

• Compatible alternative to Cisco QDD-400-CU2.5M
• 400G connectivity at 400Gbps
• Interface configuration: QSFP-DD to QSFP-DD
• Fixed length and part number: 2.5m (8ft), QDD-400-CU2.5M
• Cable construction: Passive Twinax
• Conductor specification: 26AWG
• Maximum power consumption: 0.1W Per End
• Minimum bend radius: 57mm

The listed modulation format is 8x 50Gbps PAM4. Both host interfaces must be configured for the same aggregate rate and lane arrangement. A connector that fits mechanically does not by itself guarantee that the remote port supports this encoding or breakout mode.

A passive DAC has no separate optical conversion stage. Its low-power, low-latency operation is useful for short equipment links, but the assembly must remain within the length and signaling mode accepted by both hosts.

The 2.5m (8ft) version is useful when a two-metre run would leave insufficient working slack. Before installation, check the complete horizontal and vertical path so that QDD-400-CU2.5M reaches both ports without tension at either connector.

QDD-400-CU2.5M occupies the middle of this family between QDD-400-CU2M at 2m (7ft) and QDD-400-CU3M at 3m (10ft). It adds 0.5m over the shorter option for extra routing clearance, while the next longer version adds another 0.5m. Measure the managed path and choose this version when its reach is sufficient without creating the slack associated with the longer assembly.

The rated power consumption is 0.1W Per End. Include this load in the host-port power and thermal budget, especially in densely populated switches. Maintain front-panel clearance and do not bundle the cable so tightly that it obstructs airflow around the connectors.

This assembly uses 26AWG conductors, PET jacket, minimum bend radius 57mm. These mechanical characteristics affect how the cable should be dressed behind the equipment. Avoid sharp edges, excessive ties and repeated tight bends close to the connector boots.

The intended application is 400G Ethernet. Listed interface and protocol references include IEEE 802.3cd, QSFP-DD MSA, CMIS 4.0. Confirm that the host firmware and port configuration support the same operating mode.

Each QDD-400-CU2.5M compatible cable is powered up on a suitable test interface rather than checked only for continuity. We confirm the expected identification and observe electrical continuity, link stability and diagnostic readouts. Because operating systems can apply different qualification rules by hardware revision, the intended Cisco platform should be included with the order.

This product is ordered as QDD-400-CU2.5M in 2.5m (8ft). Include the equipment model and software release if you would like a pre-order compatibility review. Other lengths use different part numbers and should not be substituted into the same order line.

Quality control includes connector appearance, cable identification and functional verification. Packing materials are selected to keep the connector housings and cable boots from taking impact during transport, and the coil is not compressed into an undersized bundle. Volume orders can include customer-specific labels and packing documentation.

Lead time for ordinary configurations is normally one to three working days, while production quantities are confirmed with the order. We can arrange express courier or economy freight according to destination and carton volume, or hand the shipment to your appointed logistics provider.