The Ruskin BTR-250 heavy-duty isolation damper is suited for system containment or decontamination applications found in laboratories, medical facilities, clean rooms and federal buildings. Designed to provide bubble-tight airflow leakage performance in systems with up to 10 inches water gauge pressure, the BTR-250 meets the requirements of the bubble test as described in AMCA Standard 500-D. Available in sizes ranging from 4 to 36 inches in diameter, the product includes a flanged channel frame for easy installation. Although the BTR-250 built to standard construction includes round flanges, Ruskin offers this model with an optional square flange design to support job-site mounting challenges. Additional options include factory-drilled mounting hole patterns in flanges, factory-supplied and mounted actuators, and switches.