The HTD-640 heavy duty industrial air control damper qualified for use in tunnel and transit systems. This model has a double flanged frame and features mechanically fastened silicone blade seals and stainless steel jamb seals.

• Meets the requirements of NFPA-130, 502, and UL 555S
• Blade type: Aluminum extruded airfoil
• Pressure: Up to 24 in. wg structural integrity; Up to 12 in. leakage and operability
• Velocity: Up to 4000 fpm
• Temperature: 250°F continuous not including actuator; 482°F for 1 hour (NFPA-130)