Survivor Filter Extra Replacement Filters for The PRO Portable Water Filter (Extra Pre-Filter Kit) EXTENDS THE LIFE OF YOUR PRO: Greatly extends the life of the PRO internal Carbon and Ultra Filter, by Pre-Treating the Water with a 0.1 Micron Filter, before it gets to the Carbon and 0.01 Micron Internal Ultra Filter of the PRO. 100,000 LITER GAURANTEE: Can be easily cleaned after every trip up to 100,000 Liters (26, 417 Gallons) for re-usable enjoyment PRE-FILTERS CONTAMINANTS: The 0.1 Micron Ultra Filter Pre-Filter acts like a barrier to help remove Pollen, Algae, Large Particles, Giardia, E. Coli, Protozoan Cysts, Cryptosporidium, Toxin and Heavy Metals UPGRADED HOSES, CLIP AND CARRY BAG: Comes with Extended Hoses and a Hose Clip PLUS a Zip Lock Carrying Case with Strap.