Designs 1221-DOW and 1221-OW are "out of wall" high efficiency mix fireplace/smoke damper precisely made for purposes where the damper can't be put in inside the plane of your wall or ground. They capabilities Nailor’s exclusive inter-locking double pores and skin airfoil blade design that gets rid of combustible seals and delivers flame https://dampersforindustrialsecto79901.newbigblog.com/43404409/the-heavy-duty-stainless-steel-damper-manufacturers-diaries