Ventilator and radiator maker Warderly International Holdings is seeking to raise HK$50 million to HK$100 million through an initial public offering (IPO) on the main board of Hong Kong Exchanges and Clearing next month to fund expansion. The contract manufacturer sells to more than 90 clients including major chain-store operators such as Wal-Mart. Chairman Yeung Kui-wong said his company was eyeing the growing demand for its ventilators installed with air-cleaning devices for future growth. The firm claims to have achieved a 43 per cent gross profit margin and net profit margin of 25 per cent during the 12 months to April this year. Mr Yeung attributed the high margins to a vertically integrated production and sales system. The company plans to launch a ventilator with air-cleaning functions next year. Warderly produces about three million ventilators a year, or 2 to 3 per cent of the annual global demand of about 100 million units. The company also makes one million radiators and about two million small home appliances a year. The firm will use the IPO proceeds mainly to expand annual production capacity and fund research and development. The company made a net profit of HK$51 million on turnover of HK$200 million in the 12 months to April 30.