This type of hydraulic valve is called a solenoid-operated cartridge valve and is designed to be screwed into a hydraulic system. It is a normally closed two-way valve, which means it only allows flow when the solenoid valve is energized. The valve is a poppet valve type, which means it uses a conical plug to control flow. It is designed for load holding or blocking functions, ensuring loads remain in place. The valve is designed to have extremely low internal leakage, minimizing any unintended fluid flow.