It contains a lot of low level discovery rules (23 rules) for FANs, disks, CPU, arrays and etc.
HP Chassis:
Array Accelerators
Array Controllers
Enclosure Managers
Enclosures
FANs
General
Logical Drives
Network Connectors
Network Interfaces
Physical Drives
Power Supplies
Server Rack Blades
Temperature Sensors

It requires HP MIB files!