The True 800306 Refrigerator Cooler Control with Knob & Plate and 3/8" x 1-1/2" coiled bulb is designed to help maintain consistent refrigerator temperatures for reliable cooling performance. It works by sensing the internal temperature through the coiled bulb and automatically regulating the refrigeration cycle to keep the desired cooling level. The included knob and plate allow for ... https://partsfe.com/800306-true-cooler-control-9531-48