Directional poppet valves can operate at a maximum operating pressure of up to 1,000 bar. Directional poppet valves are directional control valves that are fitted into housing bores with a threaded connection. This is why they are often referred to as hydraulic cartridge valves. The moveable seating elements may consist of balls, poppets or plates.
Key features of hydraulic cartridge valves: 

The design permits the valve to become more tightly sealed when operating pressure increases. The maximum flow of cartridge valves is limited compared to spool valves. Larger flows would require larger cartridges to fit into housing bores; the threaded connection will not hold. 
Typical parameters of poppet valves are:

Directional poppet valves can operate at a maximum operating pressure of up to 1,000 bar. Directional poppet valves are directional control valves that are fitted into housing bores with a threaded connection. This is why they are often referred to as hydraulic cartridge valves. The moveable seating elements may consist of balls, poppets or plates.
Key features of hydraulic cartridge valves: 

The design permits the valve to become more tightly sealed when operating pressure increases. The maximum flow of cartridge valves is limited compared to spool valves. Larger flows would require larger cartridges to fit into housing bores; the threaded connection will not hold. 
Typical parameters of poppet valves are: