Replacement cartridges kit for the Precision-RO 5-Stage Reverse Osmosis Water Treatment System: Compact and Lightweight - Designed to take up less space under the sink, the complete system, including tank, is approximately the same height and width as a standard two gallon tank and valve assembly. The entire system is less than 14 inches in depth and can be lifted easily with one hand. The small footprint of this single vessel system makes it easier to install in cramped kitchen cabinetry; More Water To The Tank, Less Water To The Drain - The single vessel system takes advantage of our new, higher flow membranes. A unique flow path gives this system a superior brine to product ratio. The combination of the two means more water to the tank, less water to the drain. The high flow membrane also ensures a fast tank refill. A completely drained tank will refill in a little under one hour. Pre-Plumbed - No preliminary tank or unit assembly is required. The tank, faucet, feed and drain lines are pre-plumbed in the unit and tested at the factory. Final onsite installation is faster and simpler.; Simple, Easy Cartridge Replacement - With only one P-RO Vessel, multi-stage water treatment cartridge, and one P-RO Polishing in-line filter to change once a year, the Precision-RO saves time and money in maintaining your water treatment system. Quick Connect Cartridges mean fast and easy removal and replacement by consumer. Fast Flow - The Precision-RO uses the latest in system design and membrane technology to give you more water when you need it. This system delivers a 30% faster water flow from the faucet compared to older RO systems.