Tecstr ductboard series products are designed and manufactured with high density glass wool board as the base material, the outer surface is covered with moisture-proof facing, and the inner surface is made of specially treated glass fiber mat/cloth, which is specially designed for the air supply and return system of HVAC fof civil and commercial use. Tecstr ductboard series products can be quickly made into straight duct, elbow, reducing duct, T duct and other air duct components, so as to form a complete air supply system. The double density male and female die on the edge of the glass wool board can provide strong fit ability, ensuring high strenght and high density.