The Young Regulator Model 3085 is a rectangular, opposed-blade, damper. In Conjunction with a T-312 thermostat, it modulates to provide the right amount of air. It features a Honeywell 7-minute motor for slow, quiet operation. the damper has been designed for both residential and light commercial applications.
The opposed-blade design allows for more even distribution of air for a quieter system with less turbulence.