ITEM NAME:DC 12V Plastic Normally Closed Electric Solenoid Valve for Water Control #gib Store Home Promotion Hot Item Add to Fav.The solenoid valve is a normally closed N/C solenoid valve. Solenoid valves are made of high-quality plastic and brass materials with long service life. Type 2.1: Guided (one-way) solenoid valve (also known as non-filling type guide valve action or solenoid valve).