The 3M™ Aqua-Pure™ whole house large sump replacement water filter drop-in cartridge AP810-2 is a great choice in water filtration. This standard 4.5 in diameter by 20 in length drop-in cartridge is manufacturer tested and verified to reduce sediment down to 5 micron nominal. Its ideal for larger homes with at least 2.5 bathrooms. As tested and verified by manufacturers laboratory.