DEMA’s offers 2 high pressure valves, the 0453P and O453S. Both are designed for pressures from 10 psi up to 1000 psi, have brass bodies, Teflon seals, designed for 3/8” pipes and have 11/32” orifices. The only difference is the 0453S features a stainless steel piston. The high pressure valves operate the same as a pilot operated valve except the pilot port is in a separate chamber from the piston. This allows the plunger to operate closer to the top plug with more force and consequently higher opening pressure.