About this item Strong Clamp for Most Fish Tanks – Suitable for aquarium walls or top edge lips with a width of less than 3/5 inches. 6-Speed Control System – Adjust the speed with the controller to reduce water temperature by up to 2-4℃. 180° Wide Angle Bracket – Satisfy your need for multi-angle use. Quiet Cooling Fan – Noise level as low as 30-40db. Low Energy Consumption – The 12V safe voltage ensures safe use and saves electricity.