Only because you asked so nicely! Here is the info for .2 micron cartridges for an undersink water filter system.
Here is the most recent 0.2micron filter we are using:
https://goblutech.com/products/0-2-micron-water-filter-recharge-2-pack-10-inch
https://goblutech.com/products/goblutech-5-micron-high-flow-water-filters-10-x-2-5-inch-2-pack
Here is a previous set I ordered and found satisfactory.
https://www.etrailer.com/RV-Water-Filter/Clearsource/CS99FR.html
We change the 5 micron filter every 3 months at home, every 2 months at our seasonal home (much cruddier water.) This setup fits a standard 10" 2 cartridge system. We have used the .2 micron filter in an in-line cartridge in our tiny camper - we get max 4-5 weeks use before it begins to clog, but are debating whether to add the bulk and weight of a 2 filter system. We switched to the BluTech because it is what the dentist's office uses. They place bottled spring water in their reservoir, then filter it through the .2 micron filter to the drill.