Replacement twin Under Sink water filter cartridges for twin undersink water filtration systems. These are universal 9 3/4 inch water filter cartridges and fit all makes and models of 10 inch undersink water filter housings. Pack includes 1 x USA made 1 micron pre-filter plus 2nd stage your choice of CRPB .45 micron Multipure cartridge or 0.5 Micron nominal MATRIKX® + Pb1 solid carbon block water filters or CR1 Matrikx cartridge or 0.4 micron Multipure super block small bore water filter or Omnipure superblock for the effective removal of heavy metals, chemicals, chlorine, foreign organic compounds, bacteria, giardia and cryptosporidium cysts, dirt, sediment and rust,  as well as other nasties present in our water supply. All USA made and NSF certified. Please choose filter options in shopping cart below. Buy in bulk and save up to a further 30% off.