The HPE 865408-B21 HP 500-Watts Flex Slot Platinum Hot-Pluggable Power Supply Kit delivers high-efficiency (94% Platinum-certified) performance, reducing energy costs and heat output. Its hot-swappable design ensures seamless server uptime during replacements or upgrades, while low-halogen construction promotes eco-safety. Compatible with HPE ProLiant servers, it offers flexible, scalable power redundancy in a compact, tool-free design—ideal for data centers prioritizing reliability, energy savings, and minimal downtime.