Katadyn Hiker Pro Replacement Cartridge - Also fits Hiker and Base Camp. Pleated cartridge has more surface area than any other microfilter. Cartridge capacity is 300 gallons [1150 liters] depending on water quality. AntiClog technology: 129 sq in of pleated 0.3 micron glass fiber media. Cartridge Capacity: up to 300 gallons [1150 liters], depending on water quality Also fits Hiker and Base Camp.