One foot lower than 40x70x21 series, cheaper and fit more customers request. Widely used for warehouse storage, car parking, agriculture, industrial, mines. Truss Fabric Covered Buildings, Storage Buildings, Portable Garages. Model TC406020: W12.2 x L18.3 x H6.1 meters, (40 x 60 x 20 feet) Model TC407020: W12.2 x L21.4 x H6.1 meters, (40 x 70 x 20 feet) Model TC408020: W12.2 x L24.4 x H6.1 meters, (40 x 80 x 20 feet) Specification: 1. Super Strong Double Truss Style for very Heavy Load. With extra steel wire and turnbuckles for strengthen. 2. All frame is hot galvanized for Antirust. 3. Winch roll up door, door size: W4.6 x H5.2m (W15’ x H17’) 4. Fabric: 300g/m2 PE or 610g/m2 PVC with 10 years longevity, UV resistant, Fire retardant. 5. Delivery time : 7-15 Days. 6. Package: Steel Crate, or Steel sheet iron box