About Us Wolter Ventilators India Pvt. Ltd. (an ISO 9001:2008 company) is a group company of Wolter GmbH, Germany, one of the leading company having 40 Years of experience in Design & Manufacturing of Ventilation and Special Application Fans to International Standards. Manufacturing Facility: ISO 9001:2008 Centrifugal & Plug Fan: AMCA Certified for Sound & Air Performance. Axial Flow Fan: AMCA Certified for Sound & Air Performance .