Description CR Spotless Cartridges  These resin replacement cartridges are easy to install and virtually hassle-free. You can change the resin cartridges in less than 5 minutes. Simply unscrew the watertight housings and remove the spent cartridge. Then, put the replacement cartridges inside the tube and reattach it to the body of the unit. You'll receive two 20-inch replacement cartridges that will deionize approximately 100 gallons of water each. The resin media has a shelf life of 1 year.  Orders from Hawaii, Alaska, Puerto Rico, or International (Non-USA) will have an additional shipping invoice included. What You Get x1 RC2-20 Replacement Cartridge Shipping Information This item is dropshipped from CR Spotless in California. Shipping is included in the price of the product for USA buyers, and will be calculated at checkout for international buyers. Expect the lead time for all CR Spotless orders to be 3-4 weeks