Platypus GravityWorks Replacement Filter Cartridge Filters fast; 4.0 L in 2.5 minutes. Effective down to .2 microns. - removes 99.9999% of bacteria and protozoa. Meets EPA Guide Standards for the removal of bacteria and protozoa. Approximate filter life of 1500L depending on quality of water filtered. Size: 4.5"/ 14.5 cm x 1.75" / 5.75 cm.