The JBX05027 400GBASE-CR8 QSFP-DD to 4x QSFP56 direct attach copper breakout cable represents a critical infrastructure component for next-generation data center deployments. This 2.5-meter passive breakout solution directly replaces Juniper's OEM QDD-4X100G-2P5M cable while offering superior compatibility and value. **Technical Specifications:** Operating at 400GB data rates, this cable utilizes QSFP-DD (Quad Small Form Factor Pluggable Double Density) to QSFP56 connectors, enabling a single high-density port to break out into four independent 100G connections. The 28AWG twinax copper design ensures reliable signal transmission with minimal crosstalk and attenuation over the 2.5-meter distance. **Compliance & Certification:** Fully qualified to ETC 400GBASE-CR8 specifications and QSFP-DD MSA standards, this cable meets RoHS/ELV directives and carries UL and TUV certifications. Operating temperature range of 0-70°C ensures performance across diverse data center environments. **Advantages of Direct Attach Copper:** As a passive DAC solution, this cable eliminates power consumption requirements, reduces latency to near-zero levels, and provides immediate deployment without firmware compatibility concerns. Compared to active optical alternatives, copper DACs deliver superior economics for short-reach connectivity within rack or between adjacent racks. **Applications:** Ideal for high-performance computing clusters, cloud infrastructure expansion, storage array interconnects, and enterprise network core upgrades. Perfect for organizations standardizing on Juniper equipment seeking cost-effective 400G breakout connectivity. **Reliability & Support:** Manufactured in Vietnam and China with rigorous quality control, this cable includes custom brand programming availability for OEM requirements. Free standard shipping on qualifying orders, with logistics support from US distribution centers in California and South Carolina ensures rapid delivery.