The InSinkErator F-501R has been discontinued by the manufacturer. If you previously purchased the F501R you will now need to purchase the F601R. The F-601R removes more contaminants than the F-501R and fits all the same insinkerator systems.
The InSinkErator F-501R Replacement Filter reduces chlorine taste & odor, unpleasant taste & odor, cysts, and turbidity. The F501R includes 2 cartridges for use with all In-Sink-Erator filter systems, including the F-201.
Price is for 2 filters ( 12 month supply ).