Versions 1221-DOW and 1221-OW are "from wall" substantial effectiveness mix hearth/smoke damper exclusively made for applications wherever the damper cannot be put in within the plane on the wall or floor. They functions Nailor’s unique inter-locking double pores and skin airfoil blade design that removes combustible seals and presents flame and smoke seal https://josuexqfti.ssnblog.com/35981486/the-ultimate-guide-to-heavy-duty-stainless-steel-damper-manufacturers