The Wells 59010 BJ Thermostat D-Stem Adaptor helps provide a secure connection between a compatible thermostat and its control knob or shaft. Measuring 21/32" in length, this adaptor is designed to fit onto the thermostat stem and accommodate the corresponding control interface. It works by extending or adapting the thermostat’s D-shaped stem so that the control knob can properly enga... https://partsfe.ca/59010-wells-stem-adapter