Arista Networks CAB-D-D-400G-0.5 Compatible 400G QSFP-DD 8 x 50G PAM4 Passive Copper Twinax Cable, 0.5m (2ft)

Use the CAB-D-D-400G-0.5 compatible assembly where a 400G connection is required between compatible ports. This page covers the 0.5m (2ft) version only, with its own HT part number, specifications and compatibility verification.

OEM Part Number: CAB-D-D-400G-0.5HT Part Number: CAB-D-D-400G-0.5

Product Highlights

• Compatible alternative to Arista Networks CAB-D-D-400G-0.5
• 400G connectivity at 400Gbps
• Interface configuration: QSFP-DD to QSFP-DD
• Fixed length and part number: 0.5m (2ft), CAB-D-D-400G-0.5
• Cable construction: Passive Twinax
• Conductor specification: 30AWG
• Maximum power consumption: 0.1W Per End
• Minimum bend radius: 33mm

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.

The 0.5m (2ft) length is suited to closely aligned ports where excessive slack would obstruct airflow or complicate dressing. Measure the actual port-to-port path before choosing CAB-D-D-400G-0.5; even a short assembly must retain the specified bend radius and should never be pulled tight behind the equipment.

CAB-D-D-400G-0.5 is the shortest of 6 verified length options in this family. It is the preferred choice when the port positions are close and cable slack must be kept to a minimum. The next option is CAB-D-D-400G-1M at 1m (3ft), adding 0.5m for a less direct routing path; selecting it unnecessarily would leave more cable to dress.

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 30AWG conductors, PET jacket, minimum bend radius 33mm. 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.

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 assembly is configured for equipment that recognizes CAB-D-D-400G-0.5. Before shipment, we inspect both connectors and verify identification, link establishment and electrical continuity, link stability and diagnostic readouts. Host hardware and firmware revisions can affect third-party cable acceptance, so customers can provide the equipment model and software release for a pre-order compatibility review.

Quote HT part number CAB-D-D-400G-0.5 with the required quantity. The 0.5m (2ft) length is fixed for this part number; if a different length is needed, select its corresponding page and OEM reference from the length list above. Standard HT labels and project-specific packaging are available.

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.

Standard configurations normally ship within one to three working days. Worldwide courier, air freight and sea freight options are available, and shipments can also be sent on your own courier account or delivered to an appointed forwarder.