10″ x 2.5″ CERAMIC Carbon Block Filter Rating: 0.5 micron. Now we have one filter that does almost everything (except remove Fluoride). Clean and re-use this filter cartridge. The caravan market is going to love this cartridge (which fits all standard 10″ housings). Caravaners like fine filtration, just clean it down, & away you go again. Counter top filters on tank water. Tank water requires at least a 0.5 micron rating. The versatility of the applications, and the ability to remove both sediment and chemical, make this cartridge a superb solution to almost every situation.