hvac air damper 1.Martrial:ABS or HIPS 2.Removable core,4 way air flow 3.Durable,adjustable 4.easy to install hvac damper,damper hvac systems hvac duct dampers air damper system damper regulators hvac Shaping Mode: plastic injection Mould Steel: S45C, P20, 718, 718H, 2738, 738H, NAK80, SKD61, E420, etc. (For Reference)Mould Base: LKM or Self-made.Mould Components: HASCO, DME, PUNCH, JINHONG, etc ...