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1m (3ft) Cisco Compatible 400G QSFP-DD Passive Direct Attach Copper Twinax Cable
1m (3ft) Cisco Compatible 400G QSFP-DD Passive Direct Attach Copper Twinax Cable
1m (3ft) Cisco Compatible 400G QSFP-DD Passive Direct Attach Copper Twinax Cable
P/N: QDD-400G-CU
US$119.00
5
Reviews
2
Questions
safeguard
4-Year Warranty
30-Day Returns
30-Day Exchange
（1000 In Stock）

Product Highlights

Near-Zero Power, Low Latency and Insertion Loss
Tested in Targeted Switches for Superior Performance, Quality, and Reliability
Highly Reliable with No Electronics or Optical Connectors
Designed to Beyond IEEE Industry BER Standards for Reliable Operation Under Harsh Operating Conditions
Simplifies Patching and Offers a Cost-effective Way for Short Links
Compliant to QSFP-DD MSA, CMIS Rev4.0, OIF 56G PAM4
Minimum Bend Radius 33.5mm for Flexible Routing
8x50G PAM4 400GAUI-8 Electrical Interface
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Specifications
Q&A
Reviews
Resources
1m (3ft) Cisco Compatible 400G QSFP-DD Passive Direct Attach Copper Twinax Cable
The 400G QSFP-DD DAC provides a QSFP-DD-to-QSFP-DD copper direct-attach solution and it is suitable for very short links and offer a cost-effective way to establish a 400-Gigabit link between QSFP-400G ports of switches/routers within racks and across adjacent racks. This DAC is designed with ultra-low loss materials, square rings, twisted pair cable 8 wires and shell extension construction for superior mechanical properties and bending performance. It is tested in actual switching systems to ensure optimal signal integrity and the best end-to-end performance. AICPLIGHT currently offers 400G QSFP-DD DAC in lengths of 0.5, 1, 1.5, 2, 2.5, and 3 meters, ideal for SDN, ML, and Cloud Computing.
Specifications
Part Number
QDD-400-CU
Vendor Name
AICPLIGHT
Form Factor
QSFP-DD to QSFP-DD
Max Data Rate
400Gbps
Media
Copper
Cable Type
Passive Twinax
Cable Length
1m (3ft)
Wire AWG
30AWG
Minimum Bend Radius
33.5mm
Power Consumption
≤0.1W
Jacket Material
PVC (OFNR)
Temperature
0 to 70°C (32 to 158°F)
Modulation Format
8x 50Gb/s PAM4
Application
400G Ethernet
Protocols
IEEE 802.3cd, QSFP-DD MSA, CMIS 4.0
Warranty
5 Years
Certification
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Questions & Answers
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All (2) Compatibility (1)Installation (1)
Q:

How should cables be routed in a high-density rack?

by S***m on 2025-07-10 15:59:05

A:

Use cable managers to maintain airflow and prevent bending.

by CPLIGHT on 2025-07-10 16:41:46

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Q:

Can these transceivers auto-negotiate with older models?

by R***m on 2025-07-10 15:29:05

A:

Yes, backward compatibility is supported in many cases.

by CPLIGHT on 2025-07-10 16:40:25

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Customer Reviews
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All (5) Performance (1)Compatibility (1)Ease of Use (1)Customer Support (1)Value (1)
q
q***m
2025-07-01 08:51:51
Confirmed Purchase
5.0

Fully compatible with our NVIDIA ConnectX-6 NICs and Mellanox switches. No firmware warnings or handshake delays.

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Y
Y***m
2025-06-21 13:21:13
Confirmed Purchase
5.0

Used in our GPU training pod (8x H100s) to connect each server node. Latency remained sub-microsecond, even with large tensor workloads.

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d
d***m
2025-06-16 12:22:52
Confirmed Purchase
5.0

We had a shipping delay and the support team took ownership and resolved it quickly with a courier reroute.

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I
I***m
2025-06-13 14:27:41
Confirmed Purchase
5.0

High-quality interconnects at a fraction of the price of branded cables. Ideal for scaling AI clusters on a budget.

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6
6***m
2025-04-15 12:01:20
Confirmed Purchase
5.0

Plug-and-play experience was excellent. The cables came clean and ready for immediate deployment.

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