... 1.Martrial:ABS or HIPS 2.Removable core,4 way air flow 3.Durable,adjustable 4.easy to install flow damper,ventilation ... Software: AutoCAD, UG, CATIA, Solid works, etc Product Name flow damper,ventilation dampers,louver vents damper Item codeABSG001MaterialPlastic(ABS/HIPS ... control the air volume.4. Removable core, four direction air flow , the windows are assembled with each frame, the windows ...