Use the 3/8 in 2-way or 3-way splitter to customize your indoor hydroponic garden water purification system. For TallBoy or any other filter system with 3/8 in inlet tubing. This is a Y splitter or 3-way Y splitter for multiple reservoirs. Use the 3/8 in ball valve inline shut-off to customize your indoor hydroponic garden water purification system. This is used to shut off feed or outlet line to system. Use all parts for the Evolution RO1000™ and Tall Boy™ or any other systems with 3/8 in tubing.