The ADC-VDBA-TC Temperature Collar is a molded polymer accessory designed to extend the operational range of the ADC-VDB770 in very cold environments. While the ADC-VDB770 normally operates down to -30°C, the collar enables functionality down to -40°C by blocking airflow to the heat sink, helping retain internal heat. Installation involves separating the collar, placing it around the mounted doorbell's backplate, pushing it firmly against the mounting surface, and reattaching the ends