The No 503ATD metal Air-Tite starting collar with damper is available in 12 sizes from 4 in through 20 in. Air-Tite series starting collars have a gasketed flange to ensure the best possible sealing at the joint.
M&M Starting Collar With Damper, 503ATD Series, 10 in Fitting, Round Shape, Steel, Finish: Galvanized, 5-1/4 in Height, 30 ga Gauge
Catalog- Air Tite® flange with gasket
- Plated steel damper hardware with locking handle