Solenoid Hydraulic Valve

hydraulic valve
In the construction of hydraulic elevators, a valve used to regulate the flow of the fluid used to raise and lower the elevator, usually a low viscosity oil.
Irrigation zone valve which uses small flexible tubes and water under pressure to provide the actuation signal from the controller to the valve.

solenoid
A solenoid is a three-dimensional coil wound into a tightly packed helix. In physics, the term solenoid refers to a loop of wire, often wrapped around a metallic core, which produces a magnetic field when an electric current is passed through it.
The solenoid defines the packing of DNA as a 30nm fiber of chromatin and results from the helical winding of at least five nucleosome strands.
A cylindrical coil of wire acting as a magnet when carrying electric current
a coil of wire around an iron core; becomes a magnet when current passes through the coil