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 6500 to 27000 gallons in a bottom feed configuration and 18000 to 70000 gallons in a top feed configuration with see-through amber body. 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. Completely enclosed system, no special venting required. No escaping gases. NSF listed and 50 PSI maximum operating pressure. Measures 17-1/2-inch length by 21-inch height by 20-inch width.