This is a Cleansui faucet-mounted water purifier cartridge. I mistakenly purchased the wrong one. I opened one of the packages, but it has not been used, so it is a new, unused item. Since it has been opened, I will sell it at a discounted price. ◆ Compatible models HGC9SZ-AZ CSP801 CSP701 CSP601 CSPX ◆ Other compatible models CSPUD CSP2 CSP3 CSP9 CSP602 3 cartridges included ◆ Compatible models are shown in the second photo. ◆ Brand new and unused.