Interpet Air-Volution utilises the latest in sound proofing engineering to ensure the most powerful air pumps with minimal noise delivering optimum performance for the aquarium. Twin outlet with carbon air filter included and ideal for filters ornaments and airwalls. For aquariums up to 120cm (48" long) OR 4 x 12" Airwall. Air flow of 2 x 250 litres/hour and pressure (mbar) of 0.23.