Designs 1221-DOW and 1221-OW are "away from wall" high efficiency combination hearth/smoke damper precisely designed for apps where by the damper cannot be put in throughout the plane in the wall or flooring. They features Nailor’s special inter-locking double skin airfoil blade structure that removes combustible seals and supplies flame and smoke seal https://felixfwmzn.59bloggers.com/37530437/detailed-notes-on-heavy-duty-stainless-steel-damper-manufacturers