Pond One O2 Plus 4000 Air Pump (93065) 02 Plus Air Blowers from Pond One are specifically designed for outdoor use and are resistant to the perils that extreme weather can throw at them. Fitted with a 10m cable, installation is made simple in comparison to other models around. 02 Plus 4000, 8000 and 12000 air machines are extremely powerful units. With outputs of 35, 70 and 110 litres per minute these are suitable for seriously large ponds or filters to stimulate aerobic activity or simply to add more oxygen to multiple points around the pond. With the design based upon the Aqua One indoor units, quietness is a given. Outlet size is 1/2 inch. Each unit comes with a 10 gang splitter allowing multiple air stones to be run simultaneously. The diaphragms of these pumps are Japanese silicone rubber cartridges which offer excellent reliability and life expectancy. Key Features: High volume, high pressure pond air pump Enables connection of up to 10 air stones High grade long life silicone parts Twin air filters supply clean air to the pond by removing dust and pollution Aids in circulation of dead water spot 10m outdoor rated cable Available in various sizes: O2plus 4000 (93065): Max Flow Rate 2100 L/Hr O2plus 8000 (93066): Max Flow Rate 4200 L/Hr O2plus 12000 (93067): Max Flow Rate 6600 L/Hr