The HPE 775404-001 high-efficiency screw-down heatsink is a processor-cooling assembly for compatible HPE servers. Its screw-down construction identifies the mounting style, while its high-efficiency design is intended for processors rated at 135 W or higher.
The listing also states that it can be used with lower-wattage processors to help reduce power consumption. It names the HPE ProLiant DL360 Gen9 Server as a compatible model, making this part relevant when servicing or configuring that server.