Koh Brothers Eco Engineering Limited, formerly Metax Engineering Corporation Limited, is an engineering solutions group that provides engineering, procurement and construction (EPC) services for water and wastewater treatment, hydro-engineering, bio-refinery and bio-energy projects. The Company operates through two segments, which include Water and Wastewater Treatment and Hydro-Engineering, and Bio-Refinery and Bio-Energy. Its principal market is in Asia with projects from both the public and private sectors. Its bio-refinery and bio-energy division under Oiltek Sdn. Bhd. specializes in a range of conventional edible oil process plants, as well as biodiesel, pre-treatment and winter fuel plants. Through a joint venture company, Oiltek Nova Bioenergy Sdn. Bhd., the Company designs, builds and supplies biogas recovery systems to palm oil mill effluent plants in Malaysia and Indonesia. Its subsidiaries include Koh Eco Engineering Pte. Ltd., WS Bioengineering Pte. Ltd. and others.