The Nu-Calgon 6106-00 Residential HVAC Odor Block is a professional-grade odor-control solution that eliminates unpleasant smells throughout the home by treating air as it moves through the HVAC system. Unlike perfumes or cover-up products, this odor block targets the source of odors and neutralizes them, resulting in a noticeably cleaner and more inviting indoor environment. This residential HVAC odor block is engineered to combat a wide range of common indoor odors, including musty smells, pet odors, smoke, stale air, sewer, and moisture- or water-damage-related odors. By placing the odor block inside the air handler or return duct system, it continuously treats all circulated air, helping improve overall indoor air quality without affecting HVAC system performance. Installation is simple and tool-free. The self-feeding, vented package is designed to be placed near the air filter, blower compartment, or another accessible location within the return duct system. As air moves through the system, the odor block gradually evaporates, evenly distributing odor-neutralizing treatment throughout the home. For areas with stronger or persistent odors, the package can be left partially open to increase effectiveness. Designed specifically for residential HVAC applications, the Nu-Calgon 6106-00 treats systems up to 3 tons and provides consistent odor control for up to two months. Trusted by HVAC professionals and homeowners alike, this product delivers reliable, low-maintenance odor elimination, backed by Nu-Calgon's proven quality standards.