Original equipment replacement filters for Clearsource Ultra Three Canister - With VirusGuard (Item Number 118750). Includes one Clearsource rust-inhibiting filter cartridge, one .5 micron carbon block filter cartridge with high-density activated coconut shell carbon, and one VirusGuard filter. VirusGuard filter Use with Clearsource Ultra System (Item Number 118750) | Clearsource Ultra System Replacement Filters, 3-Pack