QT-Plus Series Quarter-Turn Proprietary Cartridge Systems are four-stage residential reverse osmosis systems with 50 gpm capacity. Systems have 50 gpm or greater thin film membrane and clog free brine flow control. They come with quarter-turn cartridges for easy replacement, including cartridges for sediment, carbon block, thin film membrane, and GAC post filter. Proprietary disposable, encapsulated filter cartridges have swing-out feature for easy filter change out, and automatic shut off when cartridges are removed. There's no need to disconnect tubing when replacing membranes. Systems are booster pump ready, so a booster pump may be easily added for low pressure installations. Series features Quick-Connect fittings on inlet and outlet ports, and the Inlet water fitting is adaptable to use with 3/8 compression or 1/2 compression fittings. Faucet not included.