Solenoid valve, a type of valve that applies an electrical current to actuate or shift a spool or cartridge consisting of a solenoid coil and pipe fabrication. Basically, this valve type uses an electric current to shift a pin to perform simple A/B tasks such as open/close valve spools. The designation "solenoid" means that the valve operation is electrical not manual. Maybe the easiest way to describe a solenoid valve is by thinking about an automatic car lock. The electric currents get triggered, the pin gets pushed up and the doors are unlocked. A reverse current gets triggered, the pin gets pushed down, and the doors are locked.