... / 2B stainless steel Merits: Weather resistance, strong fray resistance, fine non-viscidity, self-cleanness, high revolving sensitivity and high air venting ... scope of 0-22.5°oblique angle.Warranty: 10 yearsTask: Ventilation requires improvement in worksheds, factories, barns, stables, sheds, portable buildings ... handling units. Heat & humidity can be exhausted from the building. Non-power Ventilator