High-Flow Doulton Imperial Sterasyl Ceramic cartridge. Larger diameter (2.75" vs. 2") provides 37% more surface area than CER for higher flow rates, less pressure drop, and longer runs between cleanings.
Flow rate: approx. 1 gallon per minute
Can be used in any Pure-Earth housings, as well as industry-standard housings
Availability - Usually ships in 1-2 business days