SHELTER ) Heavy-duty and high grade powder-painted square tubes frame makes it 3-4 times firmer than the same specification of round pipes 2) Heavy-duty PVC coated fabric instead of conventional PE tarpaulin makes it deluxe and more durable 3) Doors at both ends for ease of access, also for good ventilation 4) SH-7B-500 Dimensions (L x W x H): 10 x 5.0 x 4.17m 5) Ventilation on front and rear gable.