Safe and Silent Air Delivery FiberGlass Colombia S.A. is a leader in the manufacture of fiber glass ducts for air conditioning and ventilation systems. The following products, made of compacted and bonded fiber glass, are used for ventilation and to deliver conditioned air. Duct Wrap and Aerocor: Air speeds above 2400 feet/min. and static pressure above two water column inches necessitate sheet metal ducts that comply with SMACNA specifications. This is when outer covering (Duct Wrap) and inner lining (Reinforced Aerocor) are used.