Easy to install and change as no tools are required. Simply remove the old filter and replace with the new. (It's suggested to replace the filter cartridge with a new one every 3-4 weeks) The filter cartridge is mounted in the filter pump and catches the excess dust, dirt and grime to optimise the performance and lifespan of the pump. Remove and wash the filter cartridge under a garden hose to remove loose particles from the filter's fabric. For optimum cleaning and extended filter life, use in conjunction with Dellonda Model No. DL56 Cartridge Cleaner. Improves and maintains high-quality water levels to ensure safe use of your pool. Can be used with Dellonda Model No's DL19/DL20 or any pump that is size compatible. Dimensions - Diameter: 80mm, Length: 90mm, Top Hole Diameter: 49mm, Bottom Hole Diameter: 90mm. High filtration capacity: 300gal/hr. SIMPLE INSTALLATION - Easy to install and change as no tools are required. Simply remove the old filter and replace with the new. (It's sugg