Robertshaw 5500-135M Infinite Switch While this specific model is

While this specific model is noted for no neg# fitting (typically referring to the secondary port configuration on certain variations)

it is built to withstand the rigors of commercial and residential heat exchangers

where resistance increases linearly with temperature

This OEM component serves as a direct replacement for GKT2418 and GKT2418K

including the UDX and UDZ models

Robertshaw 5500-135M Infinite Switch While this specific model isThe Robertshaw 5500 135M Infinite Switch is a high performance 120V white dial commercial control designed for precision temperature management in electric ranges, warming zones, and barbecue grills. As a voltage sensing infinite switch, this unit offers a parallel circuit design that ensures consistent heat output by regulating power through a rotary switch mechanism. This model features a 5% input at low calibration, providing stable low end control