it provides precise switching between heating and cooling modes

The foot mount design and color-coded wire leads—typically black (common)

While this is a shaded pole design

ensuring a consistent and stable flame for main burner initiation

Eaton Cutler-Hammer C321KM30 Mechanical Interlock 326058-758 it provides precise switching betweenThe Eaton Cutler Hammer C321KM30 Mechanical Interlock is a critical field installable accessory designed for Freedom Series NEMA size 00, 0, 1, and 2 starters and contactors. Engineered for horizontal mounting configurations, this heavy duty mechanical link ensures positive electrical isolation by preventing two opposing contactors from closing simultaneously. This hardware is essential for reversing motor applications and multi source power transfers