... used together with dampers.5.have foam-rubber sealant.Fixed louver outlets:1. have blades to fix direction 45 degrees 2 ... foam-rubber sealant.Outlet FK series can be the end fittings for the central-controlled a/c system andit has effects ... , easy installation, smooth surface and nice looking. The series includes: louver outlet, grilles,perforated ceiling grilles, anti-rain outlet, egg-type ...