Home water filter with Reverse Osmosis system - 5 stages from WATERTECH company. It is one of the most common types in Saudi Arabia for homes, and here is a breakdown of each visible part: Lower part - 3 initial purification stages: 1. The transparent blue filter (PP Filter): traps sand, rust, and large impurities. 2. The middle white filter (GAC Filter): activated carbon removes chlorine, taste, and odor. 3. The third white filter (CTO Filter): finer carbon block removes remaining chlorine and organic matter before it reaches the membrane. Upper part - Essential stages: 4. The blue capsule on top: it is the heart of the device - the RO membrane which removes heavy salts, harmful minerals, and bacteria by 95-99%. 5. The orange capsule: labeled ALKALINE - an alkaline stage that adjusts the pH and adds beneficial minerals after purification for better taste. Other parts included in the picture: • On the left, a SUS304 box: this is the filter faucet. SUS304 means food-grade stainless steel 304 that does not rust. • On the right, a TANKPRO box: this is the purified water collection tank, usually 12 liters or 14 gallons. The purified water collects in it to come out with strong pressure from the faucet. • The white tube roll: connection pipes and fittings. Is it good? The 5-stage system with an alkaline stage is considered excellent for Riyadh's water if the tap water has salinity or a strong chlorine taste. It gives you water very close to bottled water. How is its maintenance? • Stage 1-2-3: replaced every 3-6 months. • The blue RO membrane: every two to two and a half years. • The orange alkaline filter: approximately every year.