SPX Stone/Fenner part number VF-4009. It is a Deltrol, Pilot-Operated Solenoid Valve Cartridge. The Deltrol number that is stamped into the housing is DSV-080-2NCP-N. This is a very common valve used in many hydraulic power unit applications.
Normally-Closed, Two-Way, Two-Position, Pilot-Operated Solenoid Valve
This cartridge valve is designed with positive shut off to be used in load holding applications.