Under-sink home water purification and filtration system - installed neatly and cleanly, Mashallah. Here is a breakdown of the visible parts: 1. The white tank on the left - TANKPRO This is a pressure tank for RO water. The device produces water slowly and stores it here so that when you open the small faucet, you get a strong flow directly. 2. The three blue filters below This is the first stage (Pre-filtration): • PPF / Sediment: Removes sand, rust, and large impurities • GAC / Granular Activated Carbon: Removes chlorine, taste, and odor • CTO / Carbon Block: Confirms chlorine removal before it enters the membrane 3. The three horizontal stages above it - Aqualife • The white and blue stage above is likely the main RO membrane - this removes salts and heavy metals • The stages after it are Post Carbon + Mineral to improve taste and restore some beneficial minerals 4. The small stainless steel faucet on the sink This is a separate faucet for purified water from the regular black kitchen mixer. It's excellent so you don't consume the tank for washing dishes. 5. Connections I see the gray drain in the middle and on the left is the drain for the RO waste water, and this is normal in all reverse osmosis systems. The installation looks professional and the connections are neat. Quick maintenance tip: • The three blue filters should be changed every 6 months • The RO filter and membrane every 12-18 months depending on your usage and the salinity of Riyadh's water •