Tetra AirSilent is a very small and whisper-quiet aerator pump for aquariums up to approx. 40 litres. The special feature of this air pump is the new technology. The Tetra AirSilent operates without a membrane and works maintenance-free over a long period of time.Tetra AirSilent Maxi+ very quiet - like a whisper, noise level: 35 dbA+ complete set including outflow stone, check valve and hose+ easy attachment by suction cup outside on the glass+ compact design+ extra small dimensions (105 x 60 x 35 mm)+ low power consumption thanks to piezo effect: only 1.8 watts+ maintenance-free: no need to replace the membrane+ suitable for aquariums: 40 l to 80 l+ flow rate: 42 l/h