The NY-12-K part of MEC Relays is a type of electromagnetic relay switch. It has a 12-pole, double-throw (DPDT) contact configuration with a normally open and normally closed switch. This type of switch is used to control power to other components in a system while preventing overloads, surges, and other problems related to electricity. It is used in a variety of applications, including HVAC, lighting, heating, and refrigeration control systems. The NY-12-K is typically rated for 10A@250V AC or 15A@120V AC and comes in a standard DIN-rail mount size, making it suitable for use in industrial and commercial settings.