The CISCO N55-PAC-750W-B is a 750W AC power supply unit (PSU) designed specifically for the Cisco Nexus 5500 series switches. Featuring a back-to-front airflow configuration, it ensures that air moves in the direction compatible with data center cooling strategies, optimizing thermal efficiency and reducing cooling costs. This PSU provides a resilient power solution that enhances the overall reliability of the network infrastructure, ensuring uninterrupted operations. It is hot-swappable, allowing for maintenance or upgrades without powering down the network equipment. With built-in overvoltage, overcurrent, and short circuit protection, the N55-PAC-750W-B safeguards the switch and connected devices against power anomalies, making it a critical component for mission-critical environments.