VCD - Volume Control Damper (Quadrant Arm)
MVCD - Motorized Volume Control Damper
VCD - Volume Control Damper (Worm Gear)
RVCD - Round Volume Control Damper
NRD - Non Return Damper
PRD - Pressure Relief Damper
PRF - Pressure Relief Flap
FDc - Fire Damper (Curtain Type)
MFDl - Motorized Fire Damper (Louvre Type)
MSFD - Motorised Smoke Fire Damper
