The JBX05044 400G QSFP-DD to 4x QSFP56 breakout DAC cable represents enterprise-class networking infrastructure designed for next-generation data center architectures requiring 400GB connectivity solutions. **Product Overview** This 0.5-meter passive direct attach copper cable provides a cost-effective solution for deploying 400GBASE-CR8 connectivity in performance-critical environments. The breakout configuration allows network administrators to flexibly allocate bandwidth by converting a single 400G port into four independent 100G connections, optimizing port utilization across diverse networking topologies. **Technical Specifications** Constructed with premium 30AWG copper twinax conductors and protective plastic jacketing, the cable delivers superior signal integrity over short-reach distances. The design fully complies with IEEE ETC 400GBASE-CR8 specifications and QSFP-DD MSA standards, ensuring compatibility with certified networking equipment. Operating temperature range of 0-70°C accommodates various data center environmental conditions. **Arista Compatibility & Standards** Explicitly designed as a direct replacement for Arista part number CAB-D-4Q-400G-0.5M, this cable integrates seamlessly into existing Arista-based network architectures. The passive breakout configuration requires no active power management, reducing operational complexity and associated failure points. **Compliance & Certifications** The cable meets RoHS (Restriction of Hazardous Substances) and EU Directive 2002/95/EC requirements, supporting environmentally responsible data center operations. Multiple safety certifications including TUV and UL compliance ensure workplace safety standards. **Applications & Use Cases** Ideal for hyperscale data centers, enterprise networks, and high-performance computing environments requiring cost-effective 400GB port flexibility. The 0.5-meter length optimizes dense rack configurations while maintaining optimal signal quality. **Warranty & Support** Backed by a comprehensive 90-day limited warranty and domestic shipping from Danville, CA and Beaufort, SC locations, ensuring rapid deployment and reliable customer support.