Omron MKS2PIN-AC24 Relay 318172-701 The Honeywell 301-EM-US3 Controller is

The Honeywell 301-EM-US3 Controller is a central processing hub designed for mechanical room refrigerant gas detection and ventilation control

This OEM York S1-028-07222-000 Fixed Sheave is a single-groove drive pulley engineered for specific air handler and furnace blower assemblies

Serving as the direct engineered replacement for the 5650-049 model

As a veteran-grade HVAC ventilation part

It features a fixed bore of 1 3/16 inches

Omron MKS2PIN-AC24 Relay 318172-701 The Honeywell 301-EM-US3 Controller isThe Omron MKS2PIN AC24 is a professional grade general purpose relay engineered for high reliability industrial control and HVACR sequence circuits. As a veteran technician knows, the MK S series has been a staple in control panels for decades due to its robust 8 pin octal base design and consistent performance. This DPDT relay (Double Pole Double Throw) features a 24Vac coil and is rated for a 10 Amp switching capacity, making it a versatile choice