Greenheck has introduced a new model of its ABD pressure independent automatic balancing damper. It maintains a constant airflow by adjusting to changes in system pressure. Designed for use in both supply and exhaust applications, the ABD damper blade automatically adjusts position to account for changing pressures in the duct work. Over 20 cfm set points allow for field adjustment without the use of any additional tools. The ABD can be installed directly into round duct work without the need for any fasteners or use of any adhesive. Constructed of antimicrobial plastic to inhibit microbial growth, model ABD is UL2043 classified for flame spread and smoke development. Greenheck’s automatic balancing damper is available with a flanged grille mounting box (model ABD-GM) or with a square to round transition (model ABD-T).