What is included one 5 micron sediment filter: with only 5 micron rating, it is effective in removing dirt, rust and sand particles. One granular activated carbon (GAC) filter: adsorb chlorine, halide, organic contaminants, odors, and other impurities that contribute to bad taste and odor. One 5 micron carbon block filter: remove any remaining chlorine and organic chemicals. Further, enhance the taste of water. One post-carbon inline filter: This carbon post filter removes objectionable tastes and odors to enhance the quality of your drinking water. Compatible to most RO systems, includes watts premier, Flowmatic, puroline, crystal quest, apec, and etc. Why in Alpharetta, Georgia for over a decade, iSpring water systems LLC is a family owned company specializing in reverse osmosis water filtration systems. Our products include residential and commercial reverse osmosis (ro) systems, whole house water systems, Ultrafiltration systems, shower, faucet, and counter top filters, filter cartridges and housings, ro coolers, and kitchen faucets and fittings. Our aim is to make high quality drinking water accessible for all households. With affordable pricing, solid quality, Prompt delivery, and top notch customer service, we hope to assist in bringing you great water for years to come.