It fits directly onto the packing nut

With a cut-out temperature of 220°F and a cut-in temperature of 190°F

this kit is specifically designed for standard and slow opening pressure regulators

the GSKT-RS-1 is specifically for the RS-1-BR-1 model

Heil Quaker ICP 1160717 Defrost Board It fits directly onto theThe Heil Quaker ICP 1160717 Defrost Board is a critical OEM replacement part designed to regulate the defrost cycle in residential and commercial heat pump systems. Engineered for high reliability performance, this defrost control board is a direct functional equivalent to the ICM300, featuring the same compact footprint as the original Carrier 621 series controls. It manages time and temperature defrost logic to prevent evaporator coil icing,