This Rainbow 320 automatic chlorine/bromine in-line pool and spa feeder holds 11 large or 98 small bromine or slow dissolving trichlor tablets. Treats 6,500 to 27,000 gallons bottom feed and 18000 to 70000 gallons top feed. Uses 1/4-inch feeder hoses, control valve and fittings. Completely enclosed system, no special venting required. Installs in return line on pressure side of pump downstream of all equipment. Standard with 2-inch slip PVC fittings and adapters for 1-1/2-inch. NSF listed and 50 PSI maximum operating pressure. Measures 17-1/2-inch length by 21-inch height by 20-inch width.