... and let the warm or cold air through. Flexible air hose for air conditioning device in airport is a ... it consists of inner layer, fiber heat insulation, cover layer, anti-wear rubber strip. It has advantages ... is made of inner layer, fiber heat resistance, cover layer, metal spire, and anti-wear strip. It ... anti-friction, no agglomerate, no powder, etc.. Cover it is made by coating nylon with PVC or CR ...