SHIRUBA Activated Carbon Cartridge Replacements for PF Filters PF120, PF240, PF360, PF800, PF1000. 

2 filter cartridges per packet. 
Cartridges contain activated carbon for toxin and pollutants removal.

NOTE

• It is advised to change your activated carbon cartridges at least once a week for an aquarium with high bioload.
• Do not use activated carbon cartridges while treating an aquarium with medication